diff options
| author | Bruno Haible <bruno@clisp.org> | 2000-08-20 18:44:23 +0000 |
|---|---|---|
| committer | Bruno Haible <bruno@clisp.org> | 2000-08-20 18:44:23 +0000 |
| commit | 745d7fc2fb5401bddae806a6a889cc8c9e5646c2 (patch) | |
| tree | 483a8e4f1fd293938bdfc9e547ed8675ca95c46f /doc/gperf.html | |
| parent | 4bdae6102758a6e3805a058fc638a6c882c08e81 (diff) | |
| download | gperf-745d7fc2fb5401bddae806a6a889cc8c9e5646c2.tar.gz | |
Regenerated.
Diffstat (limited to 'doc/gperf.html')
| -rw-r--r-- | doc/gperf.html | 898 |
1 files changed, 590 insertions, 308 deletions
diff --git a/doc/gperf.html b/doc/gperf.html index 9781687..015c6d2 100644 --- a/doc/gperf.html +++ b/doc/gperf.html @@ -1,36 +1,39 @@ <HTML> <HEAD> <!-- This HTML file has been created by texi2html 1.51 - from gperf.texi on 15 April 1998 --> + from gperf.texi on 20 August 2000 --> -<TITLE>User's Guide to gperf</TITLE> +<TITLE>Perfect Hash Function Generator</TITLE> </HEAD> <BODY> -<H1>User's Guide to <CODE>gperf</CODE></H1> +<H1>User's Guide to <CODE>gperf</CODE> 2.7.2</H1> +<H2>The GNU Perfect Hash Function Generator</H2> +<H2>Edition 2.7.2, 20 August 2000</H2> +<ADDRESS>Douglas C. Schmidt</ADDRESS> <P> <P><HR><P> <H1>Table of Contents</H1> <UL> -<LI><A NAME="TOC1" HREF="gperf.html#SEC1">Introduction</A> -<LI><A NAME="TOC2" HREF="gperf.html#SEC2">GNU GENERAL PUBLIC LICENSE</A> +<LI><A NAME="TOC1" HREF="gperf.html#SEC1">GNU GENERAL PUBLIC LICENSE</A> <UL> -<LI><A NAME="TOC3" HREF="gperf.html#SEC3">Preamble</A> -<LI><A NAME="TOC4" HREF="gperf.html#SEC4">Appendix: How to Apply These Terms to Your New Programs</A> +<LI><A NAME="TOC2" HREF="gperf.html#SEC2">Preamble</A> +<LI><A NAME="TOC3" HREF="gperf.html#SEC3">How to Apply These Terms to Your New Programs</A> </UL> -<LI><A NAME="TOC5" HREF="gperf.html#SEC5">Contributors to GNU <CODE>gperf</CODE> Utility</A> -<LI><A NAME="TOC6" HREF="gperf.html#SEC6">1 Introduction</A> -<LI><A NAME="TOC7" HREF="gperf.html#SEC7">2 Static search structures and GNU <CODE>gperf</CODE></A> -<LI><A NAME="TOC8" HREF="gperf.html#SEC8">3 High-Level Description of GNU <CODE>gperf</CODE></A> +<LI><A NAME="TOC4" HREF="gperf.html#SEC4">Contributors to GNU <CODE>gperf</CODE> Utility</A> +<LI><A NAME="TOC5" HREF="gperf.html#SEC5">1 Introduction</A> +<LI><A NAME="TOC6" HREF="gperf.html#SEC6">2 Static search structures and GNU <CODE>gperf</CODE></A> +<LI><A NAME="TOC7" HREF="gperf.html#SEC7">3 High-Level Description of GNU <CODE>gperf</CODE></A> <UL> -<LI><A NAME="TOC9" HREF="gperf.html#SEC9">3.1 Input Format to <CODE>gperf</CODE></A> +<LI><A NAME="TOC8" HREF="gperf.html#SEC8">3.1 Input Format to <CODE>gperf</CODE></A> <UL> -<LI><A NAME="TOC10" HREF="gperf.html#SEC10">3.1.1 <CODE>struct</CODE> Declarations and C Code Inclusion</A> -<LI><A NAME="TOC11" HREF="gperf.html#SEC11">3.1.2 Format for Keyword Entries</A> -<LI><A NAME="TOC12" HREF="gperf.html#SEC12">3.1.3 Including Additional C Functions</A> +<LI><A NAME="TOC9" HREF="gperf.html#SEC9">3.1.1 <CODE>struct</CODE> Declarations and C Code Inclusion</A> +<LI><A NAME="TOC10" HREF="gperf.html#SEC10">3.1.2 Format for Keyword Entries</A> +<LI><A NAME="TOC11" HREF="gperf.html#SEC11">3.1.3 Including Additional C Functions</A> </UL> -<LI><A NAME="TOC13" HREF="gperf.html#SEC13">3.2 Output Format for Generated C Code with <CODE>gperf</CODE></A> +<LI><A NAME="TOC12" HREF="gperf.html#SEC12">3.2 Output Format for Generated C Code with <CODE>gperf</CODE></A> +<LI><A NAME="TOC13" HREF="gperf.html#SEC13">3.3 Use of NUL characters</A> </UL> -<LI><A NAME="TOC14" HREF="gperf.html#SEC14">4 Options to the <CODE>gperf</CODE> Utility</A> +<LI><A NAME="TOC14" HREF="gperf.html#SEC14">4 Invoking <CODE>gperf</CODE></A> <UL> <LI><A NAME="TOC15" HREF="gperf.html#SEC15">4.1 Options that affect Interpretation of the Input File</A> <LI><A NAME="TOC16" HREF="gperf.html#SEC16">4.2 Options to specify the Language for the Output Code</A> @@ -42,30 +45,21 @@ <LI><A NAME="TOC21" HREF="gperf.html#SEC21">6 Things Still Left to Do</A> <LI><A NAME="TOC22" HREF="gperf.html#SEC22">7 Implementation Details of GNU <CODE>gperf</CODE></A> <LI><A NAME="TOC23" HREF="gperf.html#SEC23">8 Bibliography</A> +<LI><A NAME="TOC24" HREF="gperf.html#SEC24">Concept Index</A> </UL> <P><HR><P> -<H1><A NAME="SEC1" HREF="gperf.html#TOC1">Introduction</A></H1> +<H1><A NAME="SEC1" HREF="gperf.html#TOC1">GNU GENERAL PUBLIC LICENSE</A></H1> <P> -This manual documents the GNU <CODE>gperf</CODE> perfect hash function generator -utility, focusing on its features and how to use them, and how to report -bugs. - -</P> - - - -<H1><A NAME="SEC2" HREF="gperf.html#TOC2">GNU GENERAL PUBLIC LICENSE</A></H1> -<P> -Version 1, February 1989 +Version 2, June 1991 </P> <PRE> -Copyright (C) 1989 Free Software Foundation, Inc. -675 Mass Ave, Cambridge, MA 02139, USA +Copyright (C) 1989, 1991 Free Software Foundation, Inc., +59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. @@ -73,25 +67,27 @@ of this license document, but changing it is not allowed. -<H2><A NAME="SEC3" HREF="gperf.html#TOC3">Preamble</A></H2> +<H2><A NAME="SEC2" HREF="gperf.html#TOC2">Preamble</A></H2> <P> - The license agreements of most software companies try to keep users -at the mercy of those companies. By contrast, our General Public + The licenses for most software are designed to take away your +freedom to share and change it. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change free -software--to make sure the software is free for all its users. The -General Public License applies to the Free Software Foundation's -software and to any other program whose authors commit to using it. -You can use it for your programs, too. +software--to make sure the software is free for all its users. This +General Public License applies to most of the Free Software +Foundation's software and to any other program whose authors commit to +using it. (Some other Free Software Foundation software is covered by +the GNU Library General Public License instead.) You can apply it to +your programs, too. </P> <P> When we speak of free software, we are referring to freedom, not -price. Specifically, the General Public License is designed to make -sure that you have the freedom to give away or sell copies of free -software, that you receive source code or can get it if you want it, -that you can change the software or use pieces of it in new free -programs; and that you know you can do these things. +price. Our General Public Licenses are designed to make sure that you +have the freedom to distribute copies of free software (and charge for +this service if you wish), that you receive source code or can get it +if you want it, that you can change the software or use pieces of it +in new free programs; and that you know you can do these things. </P> <P> @@ -102,10 +98,11 @@ distribute copies of the software, or if you modify it. </P> <P> - For example, if you distribute copies of a such a program, whether + For example, if you distribute copies of such a program, whether gratis or for a fee, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the -source code. And you must tell them their rights. +source code. And you must show them these terms so they know their +rights. </P> <P> @@ -124,143 +121,234 @@ authors' reputations. </P> <P> + Finally, any free program is threatened constantly by software +patents. We wish to avoid the danger that redistributors of a free +program will individually obtain patent licenses, in effect making the +program proprietary. To prevent this, we have made it clear that any +patent must be licensed for everyone's free use or not licensed at all. + +</P> +<P> The precise terms and conditions for copying, distribution and modification follow. </P> <P> -TERMS AND CONDITIONS +TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION </P> <OL> <LI> -This License Agreement applies to any program or other work which -contains a notice placed by the copyright holder saying it may be -distributed under the terms of this General Public License. The -"Program", below, refers to any such program or work, and a "work based -on the Program" means either the Program or any work containing the -Program or a portion of it, either verbatim or with modifications. Each -licensee is addressed as "you". - -<LI> - -You may copy and distribute verbatim copies of the Program's source -code as you receive it, in any medium, provided that you conspicuously and -appropriately publish on each copy an appropriate copyright notice and -disclaimer of warranty; keep intact all the notices that refer to this -General Public License and to the absence of any warranty; and give any -other recipients of the Program a copy of this General Public License -along with the Program. You may charge a fee for the physical act of -transferring a copy. +This License applies to any program or other work which contains +a notice placed by the copyright holder saying it may be distributed +under the terms of this General Public License. The "Program", below, +refers to any such program or work, and a "work based on the Program" +means either the Program or any derivative work under copyright law: +that is to say, a work containing the Program or a portion of it, +either verbatim or with modifications and/or translated into another +language. (Hereinafter, translation is included without limitation in +the term "modification".) Each licensee is addressed as "you". + +Activities other than copying, distribution and modification are not +covered by this License; they are outside its scope. The act of +running the Program is not restricted, and the output from the Program +is covered only if its contents constitute a work based on the +Program (independent of having been made by running the Program). +Whether that is true depends on what the Program does. <LI> -You may modify your copy or copies of the Program or any portion of -it, and copy and distribute such modifications under the terms of Paragraph -1 above, provided that you also do the following: +You may copy and distribute verbatim copies of the Program's +source code as you receive it, in any medium, provided that you +conspicuously and appropriately publish on each copy an appropriate +copyright notice and disclaimer of warranty; keep intact all the +notices that refer to this License and to the absence of any warranty; +and give any other recipients of the Program a copy of this License +along with the Program. +You may charge a fee for the physical act of transferring a copy, and +you may at your option offer warranty protection in exchange for a fee. -<UL> <LI> -cause the modified files to carry prominent notices stating that -you changed the files and the date of any change; and +You may modify your copy or copies of the Program or any portion +of it, thus forming a work based on the Program, and copy and +distribute such modifications or work under the terms of Section 1 +above, provided that you also meet all of these conditions: + +<OL> <LI> -cause the whole of any work that you distribute or publish, that -in whole or in part contains the Program or any part thereof, either -with or without modifications, to be licensed at no charge to all -third parties under the terms of this General Public License (except -that you may choose to grant warranty protection to some or all -third parties, at your option). +You must cause the modified files to carry prominent notices +stating that you changed the files and the date of any change. <LI> -If the modified program normally reads commands interactively when -run, you must cause it, when started running for such interactive use -in the simplest and most usual way, to print or display an -announcement including an appropriate copyright notice and a notice -that there is no warranty (or else, saying that you provide a -warranty) and that users may redistribute the program under these -conditions, and telling the user how to view a copy of this General -Public License. +You must cause any work that you distribute or publish, that in +whole or in part contains or is derived from the Program or any +part thereof, to be licensed as a whole at no charge to all third +parties under the terms of this License. <LI> -You may charge a fee for the physical act of transferring a -copy, and you may at your option offer warranty protection in -exchange for a fee. -</UL> +If the modified program normally reads commands interactively +when run, you must cause it, when started running for such +interactive use in the most ordinary way, to print or display an +announcement including an appropriate copyright notice and a +notice that there is no warranty (or else, saying that you provide +a warranty) and that users may redistribute the program under +these conditions, and telling the user how to view a copy of this +License. (Exception: if the Program itself is interactive but +does not normally print such an announcement, your work based on +the Program is not required to print an announcement.) +</OL> -Mere aggregation of another independent work with the Program (or its -derivative) on a volume of a storage or distribution medium does not bring -the other work under the scope of these terms. +These requirements apply to the modified work as a whole. If +identifiable sections of that work are not derived from the Program, +and can be reasonably considered independent and separate works in +themselves, then this License, and its terms, do not apply to those +sections when you distribute them as separate works. But when you +distribute the same sections as part of a whole which is a work based +on the Program, the distribution of the whole must be on the terms of +this License, whose permissions for other licensees extend to the +entire whole, and thus to each and every part regardless of who wrote it. + +Thus, it is not the intent of this section to claim rights or contest +your rights to work written entirely by you; rather, the intent is to +exercise the right to control the distribution of derivative or +collective works based on the Program. + +In addition, mere aggregation of another work not based on the Program +with the Program (or with a work based on the Program) on a volume of +a storage or distribution medium does not bring the other work under +the scope of this License. <LI> -You may copy and distribute the Program (or a portion or derivative of -it, under Paragraph 2) in object code or executable form under the terms of -Paragraphs 1 and 2 above provided that you also do one of the following: +You may copy and distribute the Program (or a work based on it, +under Section 2) in object code or executable form under the terms of +Sections 1 and 2 above provided that you also do one of the following: -<UL> +<OL> <LI> -accompany it with the complete corresponding machine-readable -source code, which must be distributed under the terms of -Paragraphs 1 and 2 above; or, +Accompany it with the complete corresponding machine-readable +source code, which must be distributed under the terms of Sections +1 and 2 above on a medium customarily used for software interchange; or, <LI> -accompany it with a written offer, valid for at least three -years, to give any third party free (except for a nominal charge -for the cost of distribution) a complete machine-readable copy of the -corresponding source code, to be distributed under the terms of -Paragraphs 1 and 2 above; or, +Accompany it with a written offer, valid for at least three +years, to give any third party, for a charge no more than your +cost of physically performing source distribution, a complete +machine-readable copy of the corresponding source code, to be +distributed under the terms of Sections 1 and 2 above on a medium +customarily used for software interchange; or, <LI> -accompany it with the information you received as to where the -corresponding source code may be obtained. (This alternative is +Accompany it with the information you received as to the offer +to distribute corresponding source code. (This alternative is allowed only for noncommercial distribution and only if you -received the program in object code or executable form alone.) -</UL> +received the program in object code or executable form with such +an offer, in accord with Subsection b above.) +</OL> -Source code for a work means the preferred form of the work for making -modifications to it. For an executable file, complete source code means -all the source code for all modules it contains; but, as a special -exception, it need not include source code for modules which are standard -libraries that accompany the operating system on which the executable -file runs, or for standard header files or definitions files that -accompany that operating system. +The source code for a work means the preferred form of the work for +making modifications to it. For an executable work, complete source +code means all the source code for all modules it contains, plus any +associated interface definition files, plus the scripts used to +control compilation and installation of the executable. However, as a +special exception, the source code distributed need not include +anything that is normally distributed (in either source or binary +form) with the major components (compiler, kernel, and so on) of the +operating system on which the executable runs, unless that component +itself accompanies the executable. + +If distribution of executable or object code is made by offering +access to copy from a designated place, then offering equivalent +access to copy the source code from the same place counts as +distribution of the source code, even though third parties are not +compelled to copy the source along with the object code. <LI> -You may not copy, modify, sublicense, distribute or transfer the -Program except as expressly provided under this General Public License. -Any attempt otherwise to copy, modify, sublicense, distribute or transfer -the Program is void, and will automatically terminate your rights to use -the Program under this License. However, parties who have received -copies, or rights to use copies, from you under this General Public -License will not have their licenses terminated so long as such parties -remain in full compliance. +You may not copy, modify, sublicense, or distribute the Program +except as expressly provided under this License. Any attempt +otherwise to copy, modify, sublicense or distribute the Program is +void, and will automatically terminate your rights under this License. +However, parties who have received copies, or rights, from you under +this License will not have their licenses terminated so long as such +parties remain in full compliance. <LI> -By copying, distributing or modifying the Program (or any work based -on the Program) you indicate your acceptance of this license to do so, -and all its terms and conditions. +You are not required to accept this License, since you have not +signed it. However, nothing else grants you permission to modify or +distribute the Program or its derivative works. These actions are +prohibited by law if you do not accept this License. Therefore, by +modifying or distributing the Program (or any work based on the +Program), you indicate your acceptance of this License to do so, and +all its terms and conditions for copying, distributing or modifying +the Program or works based on it. <LI> Each time you redistribute the Program (or any work based on the -Program), the recipient automatically receives a license from the original -licensor to copy, distribute or modify the Program subject to these -terms and conditions. You may not impose any further restrictions on the -recipients' exercise of the rights granted herein. +Program), the recipient automatically receives a license from the +original licensor to copy, distribute or modify the Program subject to +these terms and conditions. You may not impose any further +restrictions on the recipients' exercise of the rights granted herein. +You are not responsible for enforcing compliance by third parties to +this License. + +<LI> + +If, as a consequence of a court judgment or allegation of patent +infringement or for any other reason (not limited to patent issues), +conditions are imposed on you (whether by court order, agreement or +otherwise) that contradict the conditions of this License, they do not +excuse you from the conditions of this License. If you cannot +distribute so as to satisfy simultaneously your obligations under this +License and any other pertinent obligations, then as a consequence you +may not distribute the Program at all. For example, if a patent +license would not permit royalty-free redistribution of the Program by +all those who receive copies directly or indirectly through you, then +the only way you could satisfy both it and this License would be to +refrain entirely from distribution of the Program. + +If any portion of this section is held invalid or unenforceable under +any particular circumstance, the balance of the section is intended to +apply and the section as a whole is intended to apply in other +circumstances. + +It is not the purpose of this section to induce you to infringe any +patents or other property right claims or to contest validity of any +such claims; this section has the sole purpose of protecting the +integrity of the free software distribution system, which is +implemented by public license practices. Many people have made +generous contributions to the wide range of software distributed +through that system in reliance on consistent application of that +system; it is up to the author/donor to decide if he or she is willing +to distribute software through any other system and a licensee cannot +impose that choice. + +This section is intended to make thoroughly clear what is believed to +be a consequence of the rest of this License. + +<LI> + +If the distribution and/or use of the Program is restricted in +certain countries either by patents or by copyrighted interfaces, the +original copyright holder who places the Program under this License +may add an explicit geographical distribution limitation excluding +those countries, so that distribution is permitted only in or among +countries not thus excluded. In such case, this License incorporates +the limitation as if written in the body of this License. <LI> @@ -270,11 +358,11 @@ be similar in spirit to the present version, but may differ in detail to address new problems or concerns. Each version is given a distinguishing version number. If the Program -specifies a version number of the license which applies to it and "any +specifies a version number of this License which applies to it and "any later version", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of -the license, you may choose any version ever published by the Free Software +this License, you may choose any version ever published by the Free Software Foundation. <LI> @@ -303,15 +391,15 @@ REPAIR OR CORRECTION. <LI> -IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL -ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR +IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, -INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES -ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT -LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES -SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE -WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN -ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. +INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING +OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED +TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY +YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER +PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE +POSSIBILITY OF SUCH DAMAGES. </OL> <P> @@ -320,31 +408,30 @@ END OF TERMS AND CONDITIONS </P> -<H2><A NAME="SEC4" HREF="gperf.html#TOC4">Appendix: How to Apply These Terms to Your New Programs</A></H2> +<H2><A NAME="SEC3" HREF="gperf.html#TOC3">How to Apply These Terms to Your New Programs</A></H2> <P> If you develop a new program, and you want it to be of the greatest -possible use to humanity, the best way to achieve this is to make it -free software which everyone can redistribute and change under these -terms. +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these terms. </P> <P> - To do so, attach the following notices to the program. It is safest to -attach them to the start of each source file to most effectively convey -the exclusion of warranty; and each file should have at least the -"copyright" line and a pointer to where the full notice is found. + To do so, attach the following notices to the program. It is safest +to attach them to the start of each source file to most effectively +convey the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. </P> <PRE> -<VAR>one line to give the program's name and a brief idea of what it does.</VAR> -Copyright (C) 19<VAR>yy</VAR> <VAR>name of author</VAR> +<VAR>one line to give the program's name and an idea of what it does.</VAR> +Copyright (C) <VAR>year</VAR> <VAR>name of author</VAR> -This program is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 1, or (at your option) -any later version. +This program is free software; you can redistribute it and/or +modify it under the terms of the GNU General Public License +as published by the Free Software Foundation; either version 2 +of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -353,7 +440,7 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software -Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. +Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. </PRE> <P> @@ -367,48 +454,55 @@ when it starts in an interactive mode: </P> <PRE> -Gnomovision version 69, Copyright (C) 19<VAR>yy</VAR> <VAR>name of author</VAR> -Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. -This is free software, and you are welcome to redistribute it -under certain conditions; type `show c' for details. +Gnomovision version 69, Copyright (C) <VAR>year</VAR> <VAR>name of author</VAR> +Gnomovision comes with ABSOLUTELY NO WARRANTY; for details +type `show w'. This is free software, and you are welcome +to redistribute it under certain conditions; type `show c' +for details. </PRE> <P> -The hypothetical commands `show w' and `show c' should show the -appropriate parts of the General Public License. Of course, the -commands you use may be called something other than `show w' and `show -c'; they could even be mouse-clicks or menu items--whatever suits your -program. +The hypothetical commands <SAMP>`show w'</SAMP> and <SAMP>`show c'</SAMP> should show +the appropriate parts of the General Public License. Of course, the +commands you use may be called something other than <SAMP>`show w'</SAMP> and +<SAMP>`show c'</SAMP>; they could even be mouse-clicks or menu items--whatever +suits your program. </P> <P> You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the program, if -necessary. Here a sample; alter the names: +necessary. Here is a sample; alter the names: </P> <PRE> -Yoyodyne, Inc., hereby disclaims all copyright interest in the -program `Gnomovision' (a program to direct compilers to make passes -at assemblers) written by James Hacker. +Yoyodyne, Inc., hereby disclaims all copyright +interest in the program `Gnomovision' +(which makes passes at compilers) written +by James Hacker. <VAR>signature of Ty Coon</VAR>, 1 April 1989 Ty Coon, President of Vice </PRE> <P> -That's all there is to it! +This General Public License does not permit incorporating your program into +proprietary programs. If your program is a subroutine library, you may +consider it more useful to permit linking proprietary applications with the +library. If this is what you want to do, use the GNU Library General +Public License instead of this License. </P> -<H1><A NAME="SEC5" HREF="gperf.html#TOC5">Contributors to GNU <CODE>gperf</CODE> Utility</A></H1> +<H1><A NAME="SEC4" HREF="gperf.html#TOC4">Contributors to GNU <CODE>gperf</CODE> Utility</A></H1> <UL> <LI> +<A NAME="IDX1"></A> The GNU <CODE>gperf</CODE> perfect hash function generator utility was originally written in GNU C++ by Douglas C. Schmidt. It is now also available in a highly-portable "old-style" C version. The general @@ -417,7 +511,7 @@ Bostic's algorithm written in C, and distributed to net.sources around 1984. The current program is a heavily modified, enhanced, and extended implementation of Keith's basic idea, created at the University of California, Irvine. Bugs, patches, and suggestions should be reported -to <CODE><bug-gnu-utils@gnu.org></CODE> and <CODE><schmidt@ics.uci.edu></CODE>. +to <CODE><bug-gnu-utils@gnu.org></CODE>. <LI> @@ -427,22 +521,27 @@ creation. In addition, Adam de Boor and Nels Olson provided many tips and insights that greatly helped improve the quality and functionality of <CODE>gperf</CODE>. + +<LI> + +A testsuite was added by Bruno Haible. He also rewrote the output +routines for better reliability. </UL> -<H1><A NAME="SEC6" HREF="gperf.html#TOC6">1 Introduction</A></H1> +<H1><A NAME="SEC5" HREF="gperf.html#TOC5">1 Introduction</A></H1> <P> <CODE>gperf</CODE> is a perfect hash function generator written in C++. It -transforms an <VAR>n</VAR> element user-specified keyword set <VAR>W</VAR> into -a perfect hash function <VAR>F</VAR>. <VAR>F</VAR> uniquely maps keywords in -<VAR>W</VAR> onto the range 0..<VAR>k</VAR>, where <VAR>k >= n</VAR>. If -<VAR>k = n</VAR> then <VAR>F</VAR> is a <EM>minimal</EM> perfect hash function. +transforms an <VAR>n</VAR> element user-specified keyword set <VAR>W</VAR> into a +perfect hash function <VAR>F</VAR>. <VAR>F</VAR> uniquely maps keywords in +<VAR>W</VAR> onto the range 0..<VAR>k</VAR>, where <VAR>k</VAR> >= <VAR>n</VAR>. If <VAR>k</VAR> += <VAR>n</VAR> then <VAR>F</VAR> is a <EM>minimal</EM> perfect hash function. <CODE>gperf</CODE> generates a 0..<VAR>k</VAR> element static lookup table and a pair of C functions. These functions determine whether a given -character string <VAR>s</VAR> occurs in <VAR>W</VAR>, using at most one probe -into the lookup table. +character string <VAR>s</VAR> occurs in <VAR>W</VAR>, using at most one probe into +the lookup table. </P> <P> @@ -450,19 +549,18 @@ into the lookup table. lexical analyzers in several production and research compilers and language processing tools, including GNU C, GNU C++, GNU Pascal, GNU Modula 3, and GNU indent. Complete C++ source code for <CODE>gperf</CODE> is -available via anonymous ftp from <CODE>ics.uci.edu</CODE> and -<CODE>ftp.santafe.edu</CODE>. <CODE>gperf</CODE> was also distributed along with -the GNU libg++ library for several years. A highly portable, -functionally equivalent K&R C version of <CODE>gperf</CODE> is archived in -comp.sources.unix, volume 20. Finally, a paper describing -<CODE>gperf</CODE>'s design and implementation in greater detail is available -in the Second USENIX C++ Conference proceedings. +available via anonymous ftp from <CODE>ftp://ftp.gnu.org/pub/gnu/gperf/</CODE>. +A paper describing <CODE>gperf</CODE>'s design and implementation in greater +detail is available in the Second USENIX C++ Conference proceedings. </P> -<H1><A NAME="SEC7" HREF="gperf.html#TOC7">2 Static search structures and GNU <CODE>gperf</CODE></A></H1> +<H1><A NAME="SEC6" HREF="gperf.html#TOC6">2 Static search structures and GNU <CODE>gperf</CODE></A></H1> +<P> +<A NAME="IDX2"></A> +</P> <P> A <STRONG>static search structure</STRONG> is an Abstract Data Type with certain fundamental operations, e.g., <EM>initialize</EM>, <EM>insert</EM>, @@ -491,8 +589,8 @@ often locate a table entry in constant time, but typically impose additional memory overhead and exhibit poor worst case performance. </P> - <P> +<A NAME="IDX3"></A> <EM>Minimal perfect hash functions</EM> provide an optimal solution for a particular class of static search sets. A minimal perfect hash function is defined by two properties: @@ -542,7 +640,7 @@ efficiently identify their respective reserved keywords. </P> -<H1><A NAME="SEC8" HREF="gperf.html#TOC8">3 High-Level Description of GNU <CODE>gperf</CODE></A></H1> +<H1><A NAME="SEC7" HREF="gperf.html#TOC7">3 High-Level Description of GNU <CODE>gperf</CODE></A></H1> <P> The perfect hash function generator <CODE>gperf</CODE> reads a set of @@ -578,9 +676,12 @@ Experimentation is the key to getting the most from <CODE>gperf</CODE>. </P> -<H2><A NAME="SEC9" HREF="gperf.html#TOC9">3.1 Input Format to <CODE>gperf</CODE></A></H2> - +<H2><A NAME="SEC8" HREF="gperf.html#TOC8">3.1 Input Format to <CODE>gperf</CODE></A></H2> <P> +<A NAME="IDX4"></A> +<A NAME="IDX5"></A> +<A NAME="IDX6"></A> +<A NAME="IDX7"></A> You can control the input keyfile format by varying certain command-line arguments, in particular the <SAMP>`-t'</SAMP> option. The input's appearance is similar to GNU utilities <CODE>flex</CODE> and <CODE>bison</CODE> (or UNIX @@ -598,15 +699,15 @@ functions </PRE> <P> -<EM>Unlike</EM> <CODE>flex</CODE> or <CODE>bison</CODE>, all sections of <CODE>gperf</CODE>'s input -are optional. The following sections describe the input format for each -section. +<EM>Unlike</EM> <CODE>flex</CODE> or <CODE>bison</CODE>, all sections of +<CODE>gperf</CODE>'s input are optional. The following sections describe the +input format for each section. </P> -<H3><A NAME="SEC10" HREF="gperf.html#TOC10">3.1.1 <CODE>struct</CODE> Declarations and C Code Inclusion</A></H3> +<H3><A NAME="SEC9" HREF="gperf.html#TOC9">3.1.1 <CODE>struct</CODE> Declarations and C Code Inclusion</A></H3> <P> The keyword input file optionally contains a section for including @@ -614,13 +715,13 @@ arbitrary C declarations and definitions, as well as provisions for providing a user-supplied <CODE>struct</CODE>. If the <SAMP>`-t'</SAMP> option <EM>is</EM> enabled, you <EM>must</EM> provide a C <CODE>struct</CODE> as the last component in the declaration section from the keyfile file. The first -field in this struct must be a <CODE>char *</CODE> identifier called <SAMP>`name'</SAMP>, -although it is possible to modify this field's name with the <SAMP>`-K'</SAMP> -option described below. +field in this struct must be a <CODE>char *</CODE> or <CODE>const char *</CODE> +identifier called <SAMP>`name'</SAMP>, although it is possible to modify this +field's name with the <SAMP>`-K'</SAMP> option described below. </P> <P> -Here is simple example, using months of the year and their attributes as +Here is a simple example, using months of the year and their attributes as input: </P> @@ -643,17 +744,20 @@ december, 12, 31, 31 </PRE> <P> -Separating the <CODE>struct</CODE> declaration from the list of key words and -other fields are a pair of consecutive percent signs, <CODE>%%</CODE>, +<A NAME="IDX8"></A> +Separating the <CODE>struct</CODE> declaration from the list of keywords and +other fields are a pair of consecutive percent signs, <SAMP>`%%'</SAMP>, appearing left justified in the first column, as in the UNIX utility <CODE>lex</CODE>. </P> <P> +<A NAME="IDX9"></A> +<A NAME="IDX10"></A> Using a syntax similar to GNU utilities <CODE>flex</CODE> and <CODE>bison</CODE>, it is possible to directly include C source text and comments verbatim into the generated output file. This is accomplished by enclosing the region -inside left-justified surrounding <CODE>%{</CODE>, <CODE>%}</CODE> pairs. Here is +inside left-justified surrounding <SAMP>`%{'</SAMP>, <SAMP>`%}'</SAMP> pairs. Here is an input fragment based on the previous example that illustrates this feature: @@ -689,7 +793,7 @@ april, 4, 30, 30 -<H3><A NAME="SEC11" HREF="gperf.html#TOC11">3.1.2 Format for Keyword Entries</A></H3> +<H3><A NAME="SEC10" HREF="gperf.html#TOC10">3.1.2 Format for Keyword Entries</A></H3> <P> The second keyfile format section contains lines of keywords and any @@ -700,16 +804,19 @@ in the first column is considered a comment. Everything following the </P> <P> The first field of each non-comment line is always the key itself. It -should be given as a simple name, i.e., without surrounding -string quotation marks, and be left-justified flush against the first -column. In this context, a "field" is considered to extend up to, but +can be given in two ways: as a simple name, i.e., without surrounding +string quotation marks, or as a string enclosed in double-quotes, in +C syntax, possibly with backslash escapes like <CODE>\"</CODE> or <CODE>\234</CODE> +or <CODE>\xa8</CODE>. In either case, it must start right at the beginning +of the line, without leading whitespace. +In this context, a "field" is considered to extend up to, but not include, the first blank, comma, or newline. Here is a simple example taken from a partial list of C reserved words: </P> <PRE> -# These are a few C reserved words, see the c.<CODE>gperf</CODE> file +# These are a few C reserved words, see the c.gperf file # for a complete list of ANSI C reserved words. unsigned sizeof @@ -723,7 +830,7 @@ return </PRE> <P> -Note that unlike <CODE>flex</CODE> or <CODE>bison</CODE> the first <CODE>%%</CODE> marker +Note that unlike <CODE>flex</CODE> or <CODE>bison</CODE> the first <SAMP>`%%'</SAMP> marker may be elided if the declaration section is empty. </P> @@ -739,12 +846,12 @@ one contain keyword attributes. </P> -<H3><A NAME="SEC12" HREF="gperf.html#TOC12">3.1.3 Including Additional C Functions</A></H3> +<H3><A NAME="SEC11" HREF="gperf.html#TOC11">3.1.3 Including Additional C Functions</A></H3> <P> The optional third section also corresponds closely with conventions found in <CODE>flex</CODE> and <CODE>bison</CODE>. All text in this section, -starting at the final <CODE>%%</CODE> and extending to the end of the input +starting at the final <SAMP>`%%'</SAMP> and extending to the end of the input file, is included verbatim into the generated output file. Naturally, it is your responsibility to ensure that the code contained in this section is valid C. @@ -752,81 +859,128 @@ section is valid C. </P> -<H2><A NAME="SEC13" HREF="gperf.html#TOC13">3.2 Output Format for Generated C Code with <CODE>gperf</CODE></A></H2> - +<H2><A NAME="SEC12" HREF="gperf.html#TOC12">3.2 Output Format for Generated C Code with <CODE>gperf</CODE></A></H2> <P> -Several options control how the generated C code appears on the standard -output. Two C function are generated. They are called <CODE>hash</CODE> and -<CODE>in_word_set</CODE>, although you may modify the name for -<CODE>in_word_set</CODE> with a command-line option. Both functions require -two arguments, a string, <CODE>char *</CODE> <VAR>str</VAR>, and a length -parameter, <CODE>int</CODE> <VAR>len</VAR>. Their default function prototypes are -as follows: +<A NAME="IDX11"></A> </P> +<P> +Several options control how the generated C code appears on the standard +output. Two C function are generated. They are called <CODE>hash</CODE> and +<CODE>in_word_set</CODE>, although you may modify their names with a command-line +option. Both functions require two arguments, a string, <CODE>char *</CODE> +<VAR>str</VAR>, and a length parameter, <CODE>int</CODE> <VAR>len</VAR>. Their default +function prototypes are as follows: -<PRE> -static int hash (char *str, int len); -int in_word_set (char *str, int len); -</PRE> - +</P> <P> +<DL> +<DT><U>Function:</U> unsigned int <B>hash</B> <I>(const char * <VAR>str</VAR>, unsigned int <VAR>len</VAR>)</I> +<DD><A NAME="IDX12"></A> By default, the generated <CODE>hash</CODE> function returns an integer value created by adding <VAR>len</VAR> to several user-specified <VAR>str</VAR> key positions indexed into an <STRONG>associated values</STRONG> table stored in a local static array. The associated values table is constructed -internally by <CODE>gperf</CODE> and later output as a static local C array called -<VAR>hash_table</VAR>; its meaning and properties are described below. -See section <A HREF="gperf.html#SEC22">7 Implementation Details of GNU <CODE>gperf</CODE></A>. The relevant key positions are specified via the -<SAMP>`-k'</SAMP> option when running <CODE>gperf</CODE>, as detailed in the <EM>Options</EM> -section below. See section <A HREF="gperf.html#SEC14">4 Options to the <CODE>gperf</CODE> Utility</A>. +internally by <CODE>gperf</CODE> and later output as a static local C array +called <SAMP>`hash_table'</SAMP>; its meaning and properties are described below +(see section <A HREF="gperf.html#SEC22">7 Implementation Details of GNU <CODE>gperf</CODE></A>). The relevant key positions are specified via +the <SAMP>`-k'</SAMP> option when running <CODE>gperf</CODE>, as detailed in the +<EM>Options</EM> section below(see section <A HREF="gperf.html#SEC14">4 Invoking <CODE>gperf</CODE></A>). +</DL> + +</P> +<P> +<DL> +<DT><U>Function:</U> <B>in_word_set</B> <I>(const char * <VAR>str</VAR>, unsigned int <VAR>len</VAR>)</I> +<DD><A NAME="IDX13"></A> +If <VAR>str</VAR> is in the keyword set, returns a pointer to that +keyword. More exactly, if the option <SAMP>`-t'</SAMP> was given, it returns +a pointer to the matching keyword's structure. Otherwise it returns +<CODE>NULL</CODE>. +</DL> </P> <P> -Two options, <SAMP>`-g'</SAMP> (assume you are compiling with GNU C and its -<CODE>inline</CODE> feature) and <SAMP>`-a'</SAMP> (assume ANSI C-style function -prototypes), alter the content of both the generated <CODE>hash</CODE> and -<CODE>in_word_set</CODE> routines. However, function <CODE>in_word_set</CODE> may -be modified more extensively, in response to your option settings. The -options that affect the <CODE>in_word_set</CODE> structure are: +If the option <SAMP>`-c'</SAMP> is not used, <VAR>str</VAR> must be a NUL terminated +string of exactly length <VAR>len</VAR>. If <SAMP>`-c'</SAMP> is used, <VAR>str</VAR> must +simply be an array of <VAR>len</VAR> characters and does not need to be NUL +terminated. </P> +<P> +The code generated for these two functions is affected by the following +options: -<UL> +</P> <DL COMPACT> <DT><SAMP>`-t'</SAMP> <DD> +<DT><SAMP>`--struct-type'</SAMP> +<DD> Make use of the user-defined <CODE>struct</CODE>. -<DT><SAMP>`-S <VAR>total switch statements</VAR>'</SAMP> +<DT><SAMP>`-S <VAR>total-switch-statements</VAR>'</SAMP> <DD> +<DT><SAMP>`--switch=<VAR>total-switch-statements</VAR>'</SAMP> +<DD> +<A NAME="IDX14"></A> Generate 1 or more C <CODE>switch</CODE> statement rather than use a large, (and potentially sparse) static array. Although the exact time and space savings of this approach vary according to your C compiler's degree of optimization, this method often results in smaller and faster code. </DL> -</UL> <P> -If the <SAMP>`-t'</SAMP> and <SAMP>`-S'</SAMP> options are omitted, the -default action is to generate a <CODE>char *</CODE> array containing the keys, -together with additional null strings used for padding the array. By -experimenting with the various input and output options, and timing the -resulting C code, you can determine the best option choices for -different keyword set characteristics. +If the <SAMP>`-t'</SAMP> and <SAMP>`-S'</SAMP> options are omitted, the default action +is to generate a <CODE>char *</CODE> array containing the keys, together with +additional null strings used for padding the array. By experimenting +with the various input and output options, and timing the resulting C +code, you can determine the best option choices for different keyword +set characteristics. + +</P> + + +<H2><A NAME="SEC13" HREF="gperf.html#TOC13">3.3 Use of NUL characters</A></H2> +<P> +<A NAME="IDX15"></A> + +</P> +<P> +By default, the code generated by <CODE>gperf</CODE> operates on zero +terminated strings, the usual representation of strings in C. This means +that the keywords in the input file must not contain NUL characters, +and the <VAR>str</VAR> argument passed to <CODE>hash</CODE> or <CODE>in_word_set</CODE> +must be NUL terminated and have exactly length <VAR>len</VAR>. + +</P> +<P> +If option <SAMP>`-c'</SAMP> is used, then the <VAR>str</VAR> argument does not need +to be NUL terminated. The code generated by <CODE>gperf</CODE> will only +access the first <VAR>len</VAR>, not <VAR>len+1</VAR>, bytes starting at <VAR>str</VAR>. +However, the keywords in the input file still must not contain NUL +characters. + +</P> +<P> +If option <SAMP>`-l'</SAMP> is used, then the hash table performs binary +comparison. The keywords in the input file may contain NUL characters, +written in string syntax as <CODE>\000</CODE> or <CODE>\x00</CODE>, and the code +generated by <CODE>gperf</CODE> will treat NUL like any other character. +Also, in this case the <SAMP>`-c'</SAMP> option is ignored. </P> -<H1><A NAME="SEC14" HREF="gperf.html#TOC14">4 Options to the <CODE>gperf</CODE> Utility</A></H1> +<H1><A NAME="SEC14" HREF="gperf.html#TOC14">4 Invoking <CODE>gperf</CODE></A></H1> <P> There are <EM>many</EM> options to <CODE>gperf</CODE>. They were added to make the program more convenient for use with real applications. "On-line" -help is readily available via the <SAMP>`-h'</SAMP> option. Here is the complete -list of options. +help is readily available via the <SAMP>`-h'</SAMP> option. Here is the +complete list of options. </P> @@ -834,12 +988,13 @@ list of options. <H2><A NAME="SEC15" HREF="gperf.html#TOC15">4.1 Options that affect Interpretation of the Input File</A></H2> - -<UL> <DL COMPACT> -<DT><SAMP>`-e <VAR>keyword delimiter list</VAR>'</SAMP> +<DT><SAMP>`-e <VAR>keyword-delimiter-list</VAR>'</SAMP> +<DD> +<DT><SAMP>`--delimiters=<VAR>keyword-delimiter-list</VAR>'</SAMP> <DD> +<A NAME="IDX16"></A> Allows the user to provide a string containing delimiters used to separate keywords from their attributes. The default is ",\n". This option is essential if you want to use keywords that have embedded @@ -848,30 +1003,29 @@ the literal tab character. <DT><SAMP>`-t'</SAMP> <DD> +<DT><SAMP>`--struct-type'</SAMP> +<DD> Allows you to include a <CODE>struct</CODE> type declaration for generated -code. Any text before a pair of consecutive %% is consider part of the -type declaration. Key words and additional fields may follow this, one -group of fields per line. A set of examples for generating perfect hash -tables and functions for Ada, C, and G++, Pascal, and Modula 2 and 3 -reserved words are distributed with this release. +code. Any text before a pair of consecutive <SAMP>`%%'</SAMP> is considered +part of the type declaration. Keywords and additional fields may follow +this, one group of fields per line. A set of examples for generating +perfect hash tables and functions for Ada, C, C++, Pascal, Modula 2, +Modula 3 and JavaScript reserved words are distributed with this release. </DL> -</UL> <H2><A NAME="SEC16" HREF="gperf.html#TOC16">4.2 Options to specify the Language for the Output Code</A></H2> - -<UL> <DL COMPACT> -<DT><SAMP>`-L <VAR>generated language name</VAR>'</SAMP> +<DT><SAMP>`-L <VAR>generated-language-name</VAR>'</SAMP> +<DD> +<DT><SAMP>`--language=<VAR>generated-language-name</VAR>'</SAMP> <DD> Instructs <CODE>gperf</CODE> to generate code in the language specified by the option's argument. Languages handled are currently: - -<UL> <DL COMPACT> <DT><SAMP>`KR-C'</SAMP> @@ -894,7 +1048,6 @@ ANSI C. This language is understood by ANSI C compilers and C++ compilers. <DD> C++. This language is understood by C++ compilers. </DL> -</UL> The default is C. @@ -908,92 +1061,128 @@ This option is supported for compatibility with previous releases of This option is supported for compatibility with previous releases of <CODE>gperf</CODE>. It does not do anything. </DL> -</UL> <H2><A NAME="SEC17" HREF="gperf.html#TOC17">4.3 Options for fine tuning Details in the Output Code</A></H2> - -<UL> <DL COMPACT> -<DT><SAMP>`-K <VAR>key name</VAR>'</SAMP> +<DT><SAMP>`-K <VAR>key-name</VAR>'</SAMP> +<DD> +<DT><SAMP>`--slot-name=<VAR>key-name</VAR>'</SAMP> <DD> +<A NAME="IDX17"></A> This option is only useful when option <SAMP>`-t'</SAMP> has been given. By default, the program assumes the structure component identifier for the keyword is <SAMP>`name'</SAMP>. This option allows an arbitrary choice of identifier for this component, although it still must occur as the first field in your supplied <CODE>struct</CODE>. -<DT><SAMP>`-H <VAR>hash function name</VAR>'</SAMP> +<DT><SAMP>`-F <VAR>initializers</VAR>'</SAMP> +<DD> +<DT><SAMP>`--initializer-suffix=<VAR>initializers</VAR>'</SAMP> +<DD> +<A NAME="IDX18"></A> +This option is only useful when option <SAMP>`-t'</SAMP> has been given. +It permits to specify initializers for the structure members following +<VAR>key name</VAR> in empty hash table entries. The list of initializers +should start with a comma. By default, the emitted code will +zero-initialize structure members following <VAR>key name</VAR>. + +<DT><SAMP>`-H <VAR>hash-function-name</VAR>'</SAMP> +<DD> +<DT><SAMP>`--hash-fn-name=<VAR>hash-function-name</VAR>'</SAMP> <DD> Allows you to specify the name for the generated hash function. Default -name is <SAMP>`hash'</SAMP>. This option permits the use of two hash tables in the -same file. +name is <SAMP>`hash'</SAMP>. This option permits the use of two hash tables in +the same file. -<DT><SAMP>`-N <VAR>lookup function name</VAR>'</SAMP> +<DT><SAMP>`-N <VAR>lookup-function-name</VAR>'</SAMP> +<DD> +<DT><SAMP>`--lookup-fn-name=<VAR>lookup-function-name</VAR>'</SAMP> <DD> Allows you to specify the name for the generated lookup function. -Default name is <SAMP>`in_word_set'</SAMP>. This option permits completely automatic -generation of perfect hash functions, especially when multiple generated -hash functions are used in the same application. +Default name is <SAMP>`in_word_set'</SAMP>. This option permits completely +automatic generation of perfect hash functions, especially when multiple +generated hash functions are used in the same application. -<DT><SAMP>`-Z <VAR>class name</VAR>'</SAMP> +<DT><SAMP>`-Z <VAR>class-name</VAR>'</SAMP> <DD> -This option is only useful when option <SAMP>`-L C++'</SAMP> has been given. -It allows you to specify the name of generated C++ class. Default name is +<DT><SAMP>`--class-name=<VAR>class-name</VAR>'</SAMP> +<DD> +<A NAME="IDX19"></A> +This option is only useful when option <SAMP>`-L C++'</SAMP> has been given. It +allows you to specify the name of generated C++ class. Default name is <CODE>Perfect_Hash</CODE>. <DT><SAMP>`-7'</SAMP> <DD> +<DT><SAMP>`--seven-bit'</SAMP> +<DD> This option specifies that all strings that will be passed as arguments to the generated hash function and the generated lookup function will solely consist of 7-bit ASCII characters (characters in the range 0..127). (Note that the ANSI C functions <CODE>isalnum</CODE> and <CODE>isgraph</CODE> do <EM>not</EM> guarantee that a character is in this range. Only an explicit test like <SAMP>`c >= 'A' && c <= 'Z''</SAMP> guarantees this.) This was the -default in earlier versions of <CODE>gperf</CODE>; now the default is to assume -8-bit characters. +default in versions of <CODE>gperf</CODE> earlier than 2.7; now the default is +to assume 8-bit characters. <DT><SAMP>`-c'</SAMP> <DD> +<DT><SAMP>`--compare-strncmp'</SAMP> +<DD> Generates C code that uses the <CODE>strncmp</CODE> function to perform string comparisons. The default action is to use <CODE>strcmp</CODE>. <DT><SAMP>`-C'</SAMP> <DD> +<DT><SAMP>`--readonly-tables'</SAMP> +<DD> Makes the contents of all generated lookup tables constant, i.e., "readonly". Many compilers can generate more efficient code for this by putting the tables in readonly memory. <DT><SAMP>`-E'</SAMP> <DD> +<DT><SAMP>`--enum'</SAMP> +<DD> Define constant values using an enum local to the lookup function rather than with #defines. This also means that different lookup functions can reside in the same file. Thanks to James Clark <CODE><jjc@ai.mit.edu></CODE>. <DT><SAMP>`-I'</SAMP> <DD> +<DT><SAMP>`--includes'</SAMP> +<DD> Include the necessary system include file, <CODE><string.h></CODE>, at the beginning of the code. By default, this is not done; the user must include this header file himself to allow compilation of the code. <DT><SAMP>`-G'</SAMP> <DD> +<DT><SAMP>`--global'</SAMP> +<DD> Generate the static table of keywords as a static global variable, rather than hiding it inside of the lookup function (which is the default behavior). -<DT><SAMP>`-W <VAR>hash table array name</VAR>'</SAMP> +<DT><SAMP>`-W <VAR>hash-table-array-name</VAR>'</SAMP> <DD> +<DT><SAMP>`--word-array-name=<VAR>hash-table-array-name</VAR>'</SAMP> +<DD> +<A NAME="IDX20"></A> Allows you to specify the name for the generated array containing the hash table. Default name is <SAMP>`wordlist'</SAMP>. This option permits the use of two hash tables in the same file, even when the option <SAMP>`-G'</SAMP> is given. -<DT><SAMP>`-S <VAR>total switch statements</VAR>'</SAMP> +<DT><SAMP>`-S <VAR>total-switch-statements</VAR>'</SAMP> +<DD> +<DT><SAMP>`--switch=<VAR>total-switch-statements</VAR>'</SAMP> <DD> +<A NAME="IDX21"></A> Causes the generated C code to use a <CODE>switch</CODE> statement scheme, rather than an array lookup table. This can lead to a reduction in both time and space requirements for some keyfiles. The argument to this @@ -1006,6 +1195,8 @@ was inspired in part by Keith Bostic's original C program. <DT><SAMP>`-T'</SAMP> <DD> +<DT><SAMP>`--omit-struct-type'</SAMP> +<DD> Prevents the transfer of the type declaration to the output file. Use this option if the type is already defined elsewhere. @@ -1014,18 +1205,17 @@ this option if the type is already defined elsewhere. This option is supported for compatibility with previous releases of <CODE>gperf</CODE>. It does not do anything. </DL> -</UL> <H2><A NAME="SEC18" HREF="gperf.html#TOC18">4.4 Options for changing the Algorithms employed by <CODE>gperf</CODE></A></H2> - -<UL> <DL COMPACT> <DT><SAMP>`-k <VAR>keys</VAR>'</SAMP> <DD> +<DT><SAMP>`--key-positions=<VAR>keys</VAR>'</SAMP> +<DD> Allows selection of the character key positions used in the keywords' hash function. The allowable choices range between 1-126, inclusive. The positions are separated by commas, e.g., <SAMP>`-k 9,4,13,14'</SAMP>; @@ -1045,6 +1235,8 @@ referenced in the hash function. <DT><SAMP>`-l'</SAMP> <DD> +<DT><SAMP>`--compare-strlen'</SAMP> +<DD> Compare key lengths before trying a string comparison. This might cut down on the number of string comparisons made during the lookup, since keys with different lengths are never compared via <CODE>strcmp</CODE>. @@ -1052,9 +1244,13 @@ However, using <SAMP>`-l'</SAMP> might greatly increase the size of the generated C code if the lookup table range is large (which implies that the switch option <SAMP>`-S'</SAMP> is not enabled), since the length table contains as many elements as there are entries in the lookup table. +This option is mandatory for binary comparisons (see section <A HREF="gperf.html#SEC13">3.3 Use of NUL characters</A>). <DT><SAMP>`-D'</SAMP> <DD> +<DT><SAMP>`--duplicates'</SAMP> +<DD> +<A NAME="IDX22"></A> Handle keywords whose key position sets hash to duplicate values. Duplicate hash values occur for two reasons: @@ -1066,12 +1262,13 @@ Since <CODE>gperf</CODE> does not backtrack it is possible for it to process all your input keywords without finding a unique mapping for each word. However, frequently only a very small number of duplicates occur, and the majority of keys still require one probe into the table. + <LI> Sometimes a set of keys may have the same names, but possess different -attributes. With the -D option <CODE>gperf</CODE> treats all these keys as part of -an equivalence class and generates a perfect hash function with multiple -comparisons for duplicate keys. It is up to you to completely +attributes. With the -D option <CODE>gperf</CODE> treats all these keys as +part of an equivalence class and generates a perfect hash function with +multiple comparisons for duplicate keys. It is up to you to completely disambiguate the keywords by modifying the generated C code. However, <CODE>gperf</CODE> helps you out by organizing the output. </UL> @@ -1082,38 +1279,49 @@ Using this option usually means that the generated hash function is no longer perfect. On the other hand, it permits <CODE>gperf</CODE> to work on keyword sets that it otherwise could not handle. -<DT><SAMP>`-f <VAR>iteration amount</VAR>'</SAMP> +<DT><SAMP>`-f <VAR>iteration-amount</VAR>'</SAMP> <DD> -Generate the perfect hash function "fast". This decreases <CODE>gperf</CODE>'s -running time at the cost of minimizing generated table-size. The -iteration amount represents the number of times to iterate when -resolving a collision. `0' means iterate by the number of keywords. -This option is probably most useful when used in conjunction with options -<SAMP>`-D'</SAMP> and/or <SAMP>`-S'</SAMP> for <EM>large</EM> keyword sets. - -<DT><SAMP>`-i <VAR>initial value</VAR>'</SAMP> +<DT><SAMP>`--fast=<VAR>iteration-amount</VAR>'</SAMP> +<DD> +Generate the perfect hash function "fast". This decreases +<CODE>gperf</CODE>'s running time at the cost of minimizing generated +table-size. The iteration amount represents the number of times to +iterate when resolving a collision. `0' means iterate by the number of +keywords. This option is probably most useful when used in conjunction +with options <SAMP>`-D'</SAMP> and/or <SAMP>`-S'</SAMP> for <EM>large</EM> keyword sets. + +<DT><SAMP>`-i <VAR>initial-value</VAR>'</SAMP> +<DD> +<DT><SAMP>`--initial-asso=<VAR>initial-value</VAR>'</SAMP> <DD> Provides an initial <VAR>value</VAR> for the associate values array. Default is 0. Increasing the initial value helps inflate the final table size, possibly leading to more time efficient keyword lookups. Note that this option is not particularly useful when <SAMP>`-S'</SAMP> is used. Also, -<SAMP>`-i'</SAMP> is overriden when the <SAMP>`-r'</SAMP> option is used. +<SAMP>`-i'</SAMP> is overridden when the <SAMP>`-r'</SAMP> option is used. -<DT><SAMP>`-j <VAR>jump value</VAR>'</SAMP> +<DT><SAMP>`-j <VAR>jump-value</VAR>'</SAMP> +<DD> +<DT><SAMP>`--jump=<VAR>jump-value</VAR>'</SAMP> <DD> -Affects the "jump value", i.e., how far to advance the -associated character value upon collisions. <VAR>Jump value</VAR> is rounded -up to an odd number, the default is 5. If the <VAR>jump value</VAR> is 0 -<CODE>gperf</CODE> jumps by random amounts. +<A NAME="IDX23"></A> +Affects the "jump value", i.e., how far to advance the associated +character value upon collisions. <VAR>Jump-value</VAR> is rounded up to an +odd number, the default is 5. If the <VAR>jump-value</VAR> is 0 <CODE>gperf</CODE> +jumps by random amounts. <DT><SAMP>`-n'</SAMP> <DD> +<DT><SAMP>`--no-strlen'</SAMP> +<DD> Instructs the generator not to include the length of a keyword when computing its hash value. This may save a few assembly instructions in the generated lookup table. <DT><SAMP>`-o'</SAMP> <DD> +<DT><SAMP>`--occurrence-sort'</SAMP> +<DD> Reorders the keywords by sorting the keywords so that frequently occuring key position set components appear first. A second reordering pass follows so that keys with "already determined values" are placed @@ -1123,13 +1331,15 @@ produce more minimal perfect hash functions. The reason for this is that the reordering helps prune the search time by handling inevitable collisions early in the search process. On the other hand, if the number of keywords is <EM>very</EM> large using <SAMP>`-o'</SAMP> may -<EM>increase</EM> <CODE>gperf</CODE>'s execution time, since collisions will begin -earlier and continue throughout the remainder of keyword processing. -See Cichelli's paper from the January 1980 Communications of the ACM for -details. +<EM>increase</EM> <CODE>gperf</CODE>'s execution time, since collisions will +begin earlier and continue throughout the remainder of keyword +processing. See Cichelli's paper from the January 1980 Communications +of the ACM for details. <DT><SAMP>`-r'</SAMP> <DD> +<DT><SAMP>`--random'</SAMP> +<DD> Utilizes randomness to initialize the associated values table. This frequently generates solutions faster than using deterministic initialization (which starts all associated values at 0). Furthermore, @@ -1139,6 +1349,8 @@ table. If <CODE>gperf</CODE> has difficultly with a certain keyword set try usi <DT><SAMP>`-s <VAR>size-multiple</VAR>'</SAMP> <DD> +<DT><SAMP>`--size-multiple=<VAR>size-multiple</VAR>'</SAMP> +<DD> Affects the size of the generated hash table. The numeric argument for this option indicates "how many times larger or smaller" the maximum associated value range should be, in relationship to the number of keys. @@ -1167,27 +1379,30 @@ heuristic. In particular, setting this value too high slows down of values. Judicious use of the <SAMP>`-f'</SAMP> option helps alleviate this overhead, however. </DL> -</UL> <H2><A NAME="SEC19" HREF="gperf.html#TOC19">4.5 Informative Output</A></H2> - -<UL> <DL COMPACT> <DT><SAMP>`-h'</SAMP> <DD> +<DT><SAMP>`--help'</SAMP> +<DD> Prints a short summary on the meaning of each program option. Aborts further program execution. <DT><SAMP>`-v'</SAMP> <DD> +<DT><SAMP>`--version'</SAMP> +<DD> Prints out the current version number. <DT><SAMP>`-d'</SAMP> <DD> +<DT><SAMP>`--debug'</SAMP> +<DD> Enables the debugging option. This produces verbose diagnostics to "standard error" when <CODE>gperf</CODE> is executing. It is useful both for maintaining the program and for determining whether a given set of @@ -1195,7 +1410,6 @@ options is actually speeding up the search for a solution. Some useful information is dumped at the end of the program when the <SAMP>`-d'</SAMP> option is enabled. </DL> -</UL> @@ -1373,8 +1587,76 @@ Retrieving Method for Static Sets</I> Communications of the ACM, 20 Foundation, 1989. </P> + + +<H1><A NAME="SEC24" HREF="gperf.html#TOC24">Concept Index</A></H1> + +<P> +<H2>%</H2> +<DIR> +<LI><A HREF="gperf.html#IDX8"><SAMP>`%%'</SAMP></A> +<LI><A HREF="gperf.html#IDX9"><SAMP>`%{'</SAMP></A> +<LI><A HREF="gperf.html#IDX10"><SAMP>`%}'</SAMP></A> +</DIR> +<H2>a</H2> +<DIR> +<LI><A HREF="gperf.html#IDX20">Array name</A> +</DIR> +<H2>b</H2> +<DIR> +<LI><A HREF="gperf.html#IDX1">Bugs</A> +</DIR> +<H2>c</H2> +<DIR> +<LI><A HREF="gperf.html#IDX19">Class name</A> +</DIR> +<H2>d</H2> +<DIR> +<LI><A HREF="gperf.html#IDX5">Declaration section</A> +<LI><A HREF="gperf.html#IDX16">Delimiters</A> +<LI><A HREF="gperf.html#IDX22">Duplicates</A> +</DIR> +<H2>f</H2> +<DIR> +<LI><A HREF="gperf.html#IDX4">Format</A> +<LI><A HREF="gperf.html#IDX7">Functions section</A> +</DIR> +<H2>h</H2> +<DIR> +<LI><A HREF="gperf.html#IDX12">hash</A> +<LI><A HREF="gperf.html#IDX11">hash table</A> +</DIR> +<H2>i</H2> +<DIR> +<LI><A HREF="gperf.html#IDX13">in_word_set</A> +<LI><A HREF="gperf.html#IDX18">Initializers</A> +</DIR> +<H2>j</H2> +<DIR> +<LI><A HREF="gperf.html#IDX23">Jump value</A> +</DIR> +<H2>k</H2> +<DIR> +<LI><A HREF="gperf.html#IDX6">Keywords section</A> +</DIR> +<H2>m</H2> +<DIR> +<LI><A HREF="gperf.html#IDX3">Minimal perfect hash functions</A> +</DIR> +<H2>n</H2> +<DIR> +<LI><A HREF="gperf.html#IDX15">NUL</A> +</DIR> +<H2>s</H2> +<DIR> +<LI><A HREF="gperf.html#IDX17">Slot name</A> +<LI><A HREF="gperf.html#IDX2">Static search structure</A> +<LI><A HREF="gperf.html#IDX14"><CODE>switch</CODE></A>, <A HREF="gperf.html#IDX21"><CODE>switch</CODE></A> +</DIR> + +</P> <P><HR><P> -This document was generated on 15 April 1998 using the +This document was generated on 20 August 2000 using the <A HREF="http://wwwcn.cern.ch/dci/texi2html/">texi2html</A> translator version 1.51.</P> </BODY> |