diff options
Diffstat (limited to 'diff/diff.c')
| -rw-r--r-- | diff/diff.c | 1267 |
1 files changed, 1267 insertions, 0 deletions
diff --git a/diff/diff.c b/diff/diff.c new file mode 100644 index 0000000..f5d82d5 --- /dev/null +++ b/diff/diff.c @@ -0,0 +1,1267 @@ +/* GNU DIFF entry routine. + Copyright (C) 1988, 1989, 1992, 1993, 1994, 1997, 1998 Free Software Foundation, Inc. + +This file is part of GNU DIFF. + +GNU DIFF 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, or (at your option) +any later version. + +GNU DIFF is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +*/ + +/* GNU DIFF was written by Mike Haertel, David Hayes, + Richard Stallman, Len Tower, and Paul Eggert. */ + +#define GDIFF_MAIN +#include "diff.h" +#include <signal.h> +#include "error.h" +#include "getopt.h" + +#ifdef HAVE_FNMATCH +# include <fnmatch.h> /* This is supposed to be available on Posix systems */ +#else /* HAVE_FNMATCH */ +# include "fnmatch.h" /* Our substitute */ +#endif /* HAVE_FNMATCH */ + +#ifndef DEFAULT_WIDTH +#define DEFAULT_WIDTH 130 +#endif + +#ifndef GUTTER_WIDTH_MINIMUM +#define GUTTER_WIDTH_MINIMUM 3 +#endif + +/* diff.c has a real initialize_main function. */ +#ifdef initialize_main +#undef initialize_main +#endif + +static char const *filetype PARAMS((struct stat const *)); +static char *option_list PARAMS((char **, int)); +static int add_exclude_file PARAMS((char const *)); +static int ck_atoi PARAMS((char const *, int *)); +static int compare_files PARAMS((char const *, char const *, char const *, char const *, int)); +static int specify_format PARAMS((char **, char *)); +static void add_exclude PARAMS((char const *)); +static void add_regexp PARAMS((struct regexp_list **, char const *)); +static void specify_style PARAMS((enum output_style)); +static int try_help PARAMS((char const *)); +static void check_output PARAMS((FILE *)); +static void usage PARAMS((void)); +static void initialize_main PARAMS((int *, char ***)); + +/* Nonzero for -r: if comparing two directories, + compare their common subdirectories recursively. */ + +static int recursive; + +/* For debugging: don't do discard_confusing_lines. */ + +int no_discards; + +#if HAVE_SETMODE +/* I/O mode: nonzero only if using binary input/output. */ +static int binary_I_O; +#endif + +/* Return a string containing the command options with which diff was invoked. + Spaces appear between what were separate ARGV-elements. + There is a space at the beginning but none at the end. + If there were no options, the result is an empty string. + + Arguments: OPTIONVEC, a vector containing separate ARGV-elements, and COUNT, + the length of that vector. */ + +static char * +option_list (optionvec, count) + char **optionvec; /* Was `vector', but that collides on Alliant. */ + int count; +{ + int i; + size_t length = 0; + char *result; + + for (i = 0; i < count; i++) + length += strlen (optionvec[i]) + 1; + + result = xmalloc (length + 1); + result[0] = 0; + + for (i = 0; i < count; i++) + { + strcat (result, " "); + strcat (result, optionvec[i]); + } + + return result; +} + +/* Convert STR to a positive integer, storing the result in *OUT. + If STR is not a valid integer, return -1 (otherwise 0). */ +static int +ck_atoi (str, out) + char const *str; + int *out; +{ + char const *p; + for (p = str; *p; p++) + if (*p < '0' || *p > '9') + return -1; + + *out = atoi (optarg); + return 0; +} + +/* Keep track of excluded file name patterns. */ + +static char const **exclude; +static int exclude_alloc, exclude_count; + +int +excluded_filename (f) + char const *f; +{ + int i; + for (i = 0; i < exclude_count; i++) + if (fnmatch (exclude[i], f, 0) == 0) + return 1; + return 0; +} + +static void +add_exclude (pattern) + char const *pattern; +{ + if (exclude_alloc <= exclude_count) + exclude = (char const **) + (exclude_alloc == 0 + ? xmalloc ((exclude_alloc = 64) * sizeof (*exclude)) + : xrealloc (exclude, (exclude_alloc *= 2) * sizeof (*exclude))); + + exclude[exclude_count++] = pattern; +} + +static int +add_exclude_file (name) + char const *name; +{ + struct file_data f; + char *p, *q, *lim; + + f.name = optarg; + f.desc = (strcmp (optarg, "-") == 0 + ? STDIN_FILENO + : open (optarg, O_RDONLY, 0)); + if (f.desc < 0 || fstat (f.desc, &f.stat) != 0) + return -1; + + sip (&f, 1); + slurp (&f); + + for (p = f.buffer, lim = p + f.buffered_chars; p < lim; p = q) + { + q = (char *) memchr (p, '\n', lim - p); + if (!q) + q = lim; + *q++ = 0; + add_exclude (p); + } + + return close (f.desc); +} + +/* The numbers 129- that appear in the fourth element of some entries + tell the big switch in `diff_run' how to process those options. */ + +static struct option const longopts[] = +{ + {"ignore-blank-lines", 0, 0, 'B'}, + {"context", 2, 0, 'C'}, + {"ifdef", 1, 0, 'D'}, + {"show-function-line", 1, 0, 'F'}, + {"speed-large-files", 0, 0, 'H'}, + {"ignore-matching-lines", 1, 0, 'I'}, + {"label", 1, 0, 'L'}, + {"file-label", 1, 0, 'L'}, /* An alias, no longer recommended */ + {"new-file", 0, 0, 'N'}, + {"entire-new-file", 0, 0, 'N'}, /* An alias, no longer recommended */ + {"unidirectional-new-file", 0, 0, 'P'}, + {"starting-file", 1, 0, 'S'}, + {"initial-tab", 0, 0, 'T'}, + {"width", 1, 0, 'W'}, + {"text", 0, 0, 'a'}, + {"ascii", 0, 0, 'a'}, /* An alias, no longer recommended */ + {"ignore-space-change", 0, 0, 'b'}, + {"minimal", 0, 0, 'd'}, + {"ed", 0, 0, 'e'}, + {"forward-ed", 0, 0, 'f'}, + {"ignore-case", 0, 0, 'i'}, + {"paginate", 0, 0, 'l'}, + {"print", 0, 0, 'l'}, /* An alias, no longer recommended */ + {"rcs", 0, 0, 'n'}, + {"show-c-function", 0, 0, 'p'}, + {"brief", 0, 0, 'q'}, + {"recursive", 0, 0, 'r'}, + {"report-identical-files", 0, 0, 's'}, + {"expand-tabs", 0, 0, 't'}, + {"version", 0, 0, 'v'}, + {"ignore-all-space", 0, 0, 'w'}, + {"exclude", 1, 0, 'x'}, + {"exclude-from", 1, 0, 'X'}, + {"side-by-side", 0, 0, 'y'}, + {"unified", 2, 0, 'U'}, + {"left-column", 0, 0, 129}, + {"suppress-common-lines", 0, 0, 130}, + {"sdiff-merge-assist", 0, 0, 131}, + {"old-line-format", 1, 0, 132}, + {"new-line-format", 1, 0, 133}, + {"unchanged-line-format", 1, 0, 134}, + {"line-format", 1, 0, 135}, + {"old-group-format", 1, 0, 136}, + {"new-group-format", 1, 0, 137}, + {"unchanged-group-format", 1, 0, 138}, + {"changed-group-format", 1, 0, 139}, + {"horizon-lines", 1, 0, 140}, + {"help", 0, 0, 141}, + {"binary", 0, 0, 142}, + {0, 0, 0, 0} +}; + + + +int +diff_run (argc, argv, out, callbacks_arg) + int argc; + char *argv[]; + const char *out; + const struct diff_callbacks *callbacks_arg; +{ + int val; + int c; + int prev = -1; + int width = DEFAULT_WIDTH; + int show_c_function = 0; + int optind_old; + int opened_file = 0; + + callbacks = callbacks_arg; + + /* Do our initializations. */ + initialize_main (&argc, &argv); + optind_old = optind; + optind = 0; + + /* Set the jump buffer, so that diff may abort execution without + terminating the process. */ + val = setjmp (diff_abort_buf); + if (val != 0) + { + optind = optind_old; + if (opened_file) + fclose (outfile); + return val; + } + + /* Decode the options. */ + while ((c = getopt_long (argc, argv, + "0123456789abBcC:dD:efF:hHiI:lL:nNpPqrsS:tTuU:vwW:x:X:y", + longopts, 0)) != EOF) + { + switch (c) + { + /* All digits combine in decimal to specify the context-size. */ + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + case '0': + if (context == -1) + context = 0; + /* If a context length has already been specified, + more digits allowed only if they follow right after the others. + Reject two separate runs of digits, or digits after -C. */ + else if (prev < '0' || prev > '9') + fatal ("context length specified twice"); + + context = context * 10 + c - '0'; + break; + + case 'a': + /* Treat all files as text files; never treat as binary. */ + always_text_flag = 1; + break; + + case 'b': + /* Ignore changes in amount of white space. */ + ignore_space_change_flag = 1; + ignore_some_changes = 1; + ignore_some_line_changes = 1; + break; + + case 'B': + /* Ignore changes affecting only blank lines. */ + ignore_blank_lines_flag = 1; + ignore_some_changes = 1; + break; + + case 'C': /* +context[=lines] */ + case 'U': /* +unified[=lines] */ + if (optarg) + { + if (context >= 0) + fatal ("context length specified twice"); + + if (ck_atoi (optarg, &context)) + fatal ("invalid context length argument"); + } + + /* Falls through. */ + case 'c': + /* Make context-style output. */ + specify_style (c == 'U' ? OUTPUT_UNIFIED : OUTPUT_CONTEXT); + break; + + case 'd': + /* Don't discard lines. This makes things slower (sometimes much + slower) but will find a guaranteed minimal set of changes. */ + no_discards = 1; + break; + + case 'D': + /* Make merged #ifdef output. */ + specify_style (OUTPUT_IFDEF); + { + int i, err = 0; + static char const C_ifdef_group_formats[] = + "#ifndef %s\n%%<#endif /* not %s */\n%c#ifdef %s\n%%>#endif /* %s */\n%c%%=%c#ifndef %s\n%%<#else /* %s */\n%%>#endif /* %s */\n"; + char *b = xmalloc (sizeof (C_ifdef_group_formats) + + 7 * strlen(optarg) - 14 /* 7*"%s" */ + - 8 /* 5*"%%" + 3*"%c" */); + sprintf (b, C_ifdef_group_formats, + optarg, optarg, 0, + optarg, optarg, 0, 0, + optarg, optarg, optarg); + for (i = 0; i < 4; i++) + { + err |= specify_format (&group_format[i], b); + b += strlen (b) + 1; + } + if (err) + diff_error ("conflicting #ifdef formats", 0, 0); + } + break; + + case 'e': + /* Make output that is a valid `ed' script. */ + specify_style (OUTPUT_ED); + break; + + case 'f': + /* Make output that looks vaguely like an `ed' script + but has changes in the order they appear in the file. */ + specify_style (OUTPUT_FORWARD_ED); + break; + + case 'F': + /* Show, for each set of changes, the previous line that + matches the specified regexp. Currently affects only + context-style output. */ + add_regexp (&function_regexp_list, optarg); + break; + + case 'h': + /* Split the files into chunks of around 1500 lines + for faster processing. Usually does not change the result. + + This currently has no effect. */ + break; + + case 'H': + /* Turn on heuristics that speed processing of large files + with a small density of changes. */ + heuristic = 1; + break; + + case 'i': + /* Ignore changes in case. */ + ignore_case_flag = 1; + ignore_some_changes = 1; + ignore_some_line_changes = 1; + break; + + case 'I': + /* Ignore changes affecting only lines that match the + specified regexp. */ + add_regexp (&ignore_regexp_list, optarg); + ignore_some_changes = 1; + break; + + case 'l': + /* Pass the output through `pr' to paginate it. */ + paginate_flag = 1; +#if !defined(SIGCHLD) && defined(SIGCLD) +#define SIGCHLD SIGCLD +#endif +#ifdef SIGCHLD + /* Pagination requires forking and waiting, and + System V fork+wait does not work if SIGCHLD is ignored. */ + signal (SIGCHLD, SIG_DFL); +#endif + break; + + case 'L': + /* Specify file labels for `-c' output headers. */ + if (!file_label[0]) + file_label[0] = optarg; + else if (!file_label[1]) + file_label[1] = optarg; + else + fatal ("too many file label options"); + break; + + case 'n': + /* Output RCS-style diffs, like `-f' except that each command + specifies the number of lines affected. */ + specify_style (OUTPUT_RCS); + break; + + case 'N': + /* When comparing directories, if a file appears only in one + directory, treat it as present but empty in the other. */ + entire_new_file_flag = 1; + break; + + case 'p': + /* Make context-style output and show name of last C function. */ + show_c_function = 1; + add_regexp (&function_regexp_list, "^[_a-zA-Z$]"); + break; + + case 'P': + /* When comparing directories, if a file appears only in + the second directory of the two, + treat it as present but empty in the other. */ + unidirectional_new_file_flag = 1; + break; + + case 'q': + no_details_flag = 1; + break; + + case 'r': + /* When comparing directories, + recursively compare any subdirectories found. */ + recursive = 1; + break; + + case 's': + /* Print a message if the files are the same. */ + print_file_same_flag = 1; + break; + + case 'S': + /* When comparing directories, start with the specified + file name. This is used for resuming an aborted comparison. */ + dir_start_file = optarg; + break; + + case 't': + /* Expand tabs to spaces in the output so that it preserves + the alignment of the input files. */ + tab_expand_flag = 1; + break; + + case 'T': + /* Use a tab in the output, rather than a space, before the + text of an input line, so as to keep the proper alignment + in the input line without changing the characters in it. */ + tab_align_flag = 1; + break; + + case 'u': + /* Output the context diff in unidiff format. */ + specify_style (OUTPUT_UNIFIED); + break; + + case 'v': + if (callbacks && callbacks->write_stdout) + { + (*callbacks->write_stdout) ("diff - GNU diffutils version "); + (*callbacks->write_stdout) (diff_version_string); + (*callbacks->write_stdout) ("\n"); + } + else + printf ("diff - GNU diffutils version %s\n", diff_version_string); + return 0; + + case 'w': + /* Ignore horizontal white space when comparing lines. */ + ignore_all_space_flag = 1; + ignore_some_changes = 1; + ignore_some_line_changes = 1; + break; + + case 'x': + add_exclude (optarg); + break; + + case 'X': + if (add_exclude_file (optarg) != 0) + pfatal_with_name (optarg); + break; + + case 'y': + /* Use side-by-side (sdiff-style) columnar output. */ + specify_style (OUTPUT_SDIFF); + break; + + case 'W': + /* Set the line width for OUTPUT_SDIFF. */ + if (ck_atoi (optarg, &width) || width <= 0) + fatal ("column width must be a positive integer"); + break; + + case 129: + sdiff_left_only = 1; + break; + + case 130: + sdiff_skip_common_lines = 1; + break; + + case 131: + /* sdiff-style columns output. */ + specify_style (OUTPUT_SDIFF); + sdiff_help_sdiff = 1; + break; + + case 132: + case 133: + case 134: + specify_style (OUTPUT_IFDEF); + if (specify_format (&line_format[c - 132], optarg) != 0) + diff_error ("conflicting line format", 0, 0); + break; + + case 135: + specify_style (OUTPUT_IFDEF); + { + int i, err = 0; + for (i = 0; i < sizeof (line_format) / sizeof (*line_format); i++) + err |= specify_format (&line_format[i], optarg); + if (err) + diff_error ("conflicting line format", 0, 0); + } + break; + + case 136: + case 137: + case 138: + case 139: + specify_style (OUTPUT_IFDEF); + if (specify_format (&group_format[c - 136], optarg) != 0) + diff_error ("conflicting group format", 0, 0); + break; + + case 140: + if (ck_atoi (optarg, &horizon_lines) || horizon_lines < 0) + fatal ("horizon must be a nonnegative integer"); + break; + + case 141: + usage (); + if (! callbacks || ! callbacks->write_stdout) + check_output (stdout); + return 0; + + case 142: + /* Use binary I/O when reading and writing data. + On Posix hosts, this has no effect. */ +#if HAVE_SETMODE + binary_I_O = 1; +# if 0 + /* Because this code is leftover from pre-library days, + there is no way to set stdout back to the default mode + when we are done. As it turns out, I think the only + parts of CVS that pass out == NULL, and thus cause diff + to write to stdout, are "cvs diff" and "cvs rdiff". So + I'm not going to worry about this too much yet. */ + setmode (STDOUT_FILENO, O_BINARY); +# else + if (out == NULL) + error (0, 0, "warning: did not set stdout to binary mode"); +# endif +#endif + break; + + default: + return try_help (0); + } + prev = c; + } + + if (argc - optind != 2) + return try_help (argc - optind < 2 ? "missing operand" : "extra operand"); + + { + /* + * We maximize first the half line width, and then the gutter width, + * according to the following constraints: + * 1. Two half lines plus a gutter must fit in a line. + * 2. If the half line width is nonzero: + * a. The gutter width is at least GUTTER_WIDTH_MINIMUM. + * b. If tabs are not expanded to spaces, + * a half line plus a gutter is an integral number of tabs, + * so that tabs in the right column line up. + */ + int t = tab_expand_flag ? 1 : TAB_WIDTH; + int off = (width + t + GUTTER_WIDTH_MINIMUM) / (2*t) * t; + sdiff_half_width = max (0, min (off - GUTTER_WIDTH_MINIMUM, width - off)), + sdiff_column2_offset = sdiff_half_width ? off : width; + } + + if (show_c_function && output_style != OUTPUT_UNIFIED) + specify_style (OUTPUT_CONTEXT); + + if (output_style != OUTPUT_CONTEXT && output_style != OUTPUT_UNIFIED) + context = 0; + else if (context == -1) + /* Default amount of context for -c. */ + context = 3; + + if (output_style == OUTPUT_IFDEF) + { + /* Format arrays are char *, not char const *, + because integer formats are temporarily modified. + But it is safe to assign a constant like "%=" to a format array, + since "%=" does not format any integers. */ + int i; + for (i = 0; i < sizeof (line_format) / sizeof (*line_format); i++) + if (!line_format[i]) + line_format[i] = "%l\n"; + if (!group_format[OLD]) + group_format[OLD] + = group_format[UNCHANGED] ? group_format[UNCHANGED] : "%<"; + if (!group_format[NEW]) + group_format[NEW] + = group_format[UNCHANGED] ? group_format[UNCHANGED] : "%>"; + if (!group_format[UNCHANGED]) + group_format[UNCHANGED] = "%="; + if (!group_format[CHANGED]) + group_format[CHANGED] = concat (group_format[OLD], + group_format[NEW], ""); + } + + no_diff_means_no_output = + (output_style == OUTPUT_IFDEF ? + (!*group_format[UNCHANGED] + || (strcmp (group_format[UNCHANGED], "%=") == 0 + && !*line_format[UNCHANGED])) + : output_style == OUTPUT_SDIFF ? sdiff_skip_common_lines : 1); + + switch_string = option_list (argv + 1, optind - 1); + + if (callbacks && callbacks->write_output) + { + if (out != NULL) + { + diff_error ("write callback with output file", 0, 0); + return 2; + } + } + else + { + if (out == NULL) + outfile = stdout; + else + { +#if HAVE_SETMODE + /* A diff which is full of ^Z and such isn't going to work + very well in text mode. */ + if (binary_I_O) + outfile = fopen (out, "wb"); + else +#endif + outfile = fopen (out, "w"); + if (outfile == NULL) + { + perror_with_name ("could not open output file"); + return 2; + } + opened_file = 1; + } + } + + val = compare_files (0, argv[optind], 0, argv[optind + 1], 0); + + /* Print any messages that were saved up for last. */ + print_message_queue (); + + free (switch_string); + + optind = optind_old; + + if (! callbacks || ! callbacks->write_output) + check_output (outfile); + + if (opened_file) + if (fclose (outfile) != 0) + perror_with_name ("close error on output file"); + + return val; +} + +/* Add the compiled form of regexp PATTERN to REGLIST. */ + +static void +add_regexp (reglist, pattern) + struct regexp_list **reglist; + char const *pattern; +{ + struct regexp_list *r; + char const *m; + + r = (struct regexp_list *) xmalloc (sizeof (*r)); + bzero (r, sizeof (*r)); + r->buf.fastmap = xmalloc (256); + m = re_compile_pattern (pattern, strlen (pattern), &r->buf); + if (m != 0) + diff_error ("%s: %s", pattern, m); + + /* Add to the start of the list, since it's easier than the end. */ + r->next = *reglist; + *reglist = r; +} + +static int +try_help (reason) + char const *reason; +{ + if (reason) + diff_error ("%s", reason, 0); + diff_error ("Try `%s --help' for more information.", diff_program_name, 0); + return 2; +} + +static void +check_output (file) + FILE *file; +{ + if (ferror (file) || fflush (file) != 0) + fatal ("write error"); +} + +static char const * const option_help[] = { +"-i --ignore-case Consider upper- and lower-case to be the same.", +"-w --ignore-all-space Ignore all white space.", +"-b --ignore-space-change Ignore changes in the amount of white space.", +"-B --ignore-blank-lines Ignore changes whose lines are all blank.", +"-I RE --ignore-matching-lines=RE Ignore changes whose lines all match RE.", +#if HAVE_SETMODE +"--binary Read and write data in binary mode.", +#endif +"-a --text Treat all files as text.\n", +"-c -C NUM --context[=NUM] Output NUM (default 2) lines of copied context.", +"-u -U NUM --unified[=NUM] Output NUM (default 2) lines of unified context.", +" -NUM Use NUM context lines.", +" -L LABEL --label LABEL Use LABEL instead of file name.", +" -p --show-c-function Show which C function each change is in.", +" -F RE --show-function-line=RE Show the most recent line matching RE.", +"-q --brief Output only whether files differ.", +"-e --ed Output an ed script.", +"-n --rcs Output an RCS format diff.", +"-y --side-by-side Output in two columns.", +" -W NUM --width=NUM Output at most NUM (default 130) characters per line.", +" --left-column Output only the left column of common lines.", +" --suppress-common-lines Do not output common lines.", +"-DNAME --ifdef=NAME Output merged file to show `#ifdef NAME' diffs.", +"--GTYPE-group-format=GFMT Similar, but format GTYPE input groups with GFMT.", +"--line-format=LFMT Similar, but format all input lines with LFMT.", +"--LTYPE-line-format=LFMT Similar, but format LTYPE input lines with LFMT.", +" LTYPE is `old', `new', or `unchanged'. GTYPE is LTYPE or `changed'.", +" GFMT may contain:", +" %< lines from FILE1", +" %> lines from FILE2", +" %= lines common to FILE1 and FILE2", +" %[-][WIDTH][.[PREC]]{doxX}LETTER printf-style spec for LETTER", +" LETTERs are as follows for new group, lower case for old group:", +" F first line number", +" L last line number", +" N number of lines = L-F+1", +" E F-1", +" M L+1", +" LFMT may contain:", +" %L contents of line", +" %l contents of line, excluding any trailing newline", +" %[-][WIDTH][.[PREC]]{doxX}n printf-style spec for input line number", +" Either GFMT or LFMT may contain:", +" %% %", +" %c'C' the single character C", +" %c'\\OOO' the character with octal code OOO\n", +"-l --paginate Pass the output through `pr' to paginate it.", +"-t --expand-tabs Expand tabs to spaces in output.", +"-T --initial-tab Make tabs line up by prepending a tab.\n", +"-r --recursive Recursively compare any subdirectories found.", +"-N --new-file Treat absent files as empty.", +"-P --unidirectional-new-file Treat absent first files as empty.", +"-s --report-identical-files Report when two files are the same.", +"-x PAT --exclude=PAT Exclude files that match PAT.", +"-X FILE --exclude-from=FILE Exclude files that match any pattern in FILE.", +"-S FILE --starting-file=FILE Start with FILE when comparing directories.\n", +"--horizon-lines=NUM Keep NUM lines of the common prefix and suffix.", +"-d --minimal Try hard to find a smaller set of changes.", +"-H --speed-large-files Assume large files and many scattered small changes.\n", +"-v --version Output version info.", +"--help Output this help.", +0 +}; + +static void +usage () +{ + char const * const *p; + + if (callbacks && callbacks->write_stdout) + { + (*callbacks->write_stdout) ("Usage: "); + (*callbacks->write_stdout) (diff_program_name); + (*callbacks->write_stdout) (" [OPTION]... FILE1 FILE2\n\n"); + for (p = option_help; *p; p++) + { + (*callbacks->write_stdout) (" "); + (*callbacks->write_stdout) (*p); + (*callbacks->write_stdout) ("\n"); + } + (*callbacks->write_stdout) + ("\nIf FILE1 or FILE2 is `-', read standard input.\n"); + } + else + { + printf ("Usage: %s [OPTION]... FILE1 FILE2\n\n", diff_program_name); + for (p = option_help; *p; p++) + printf (" %s\n", *p); + printf ("\nIf FILE1 or FILE2 is `-', read standard input.\n"); + } +} + +static int +specify_format (var, value) + char **var; + char *value; +{ + int err = *var ? strcmp (*var, value) : 0; + *var = value; + return err; +} + +static void +specify_style (style) + enum output_style style; +{ + if (output_style != OUTPUT_NORMAL + && output_style != style) + diff_error ("conflicting specifications of output style", 0, 0); + output_style = style; +} + +static char const * +filetype (st) + struct stat const *st; +{ + /* See Posix.2 section 4.17.6.1.1 and Table 5-1 for these formats. + To keep diagnostics grammatical, the returned string must start + with a consonant. */ + + if (S_ISREG (st->st_mode)) + { + if (st->st_size == 0) + return "regular empty file"; + /* Posix.2 section 5.14.2 seems to suggest that we must read the file + and guess whether it's C, Fortran, etc., but this is somewhat useless + and doesn't reflect historical practice. We're allowed to guess + wrong, so we don't bother to read the file. */ + return "regular file"; + } + if (S_ISDIR (st->st_mode)) return "directory"; + + /* other Posix.1 file types */ +#ifdef S_ISBLK + if (S_ISBLK (st->st_mode)) return "block special file"; +#endif +#ifdef S_ISCHR + if (S_ISCHR (st->st_mode)) return "character special file"; +#endif +#ifdef S_ISFIFO + if (S_ISFIFO (st->st_mode)) return "fifo"; +#endif + + /* other Posix.1b file types */ +#ifdef S_TYPEISMQ + if (S_TYPEISMQ (st)) return "message queue"; +#endif +#ifdef S_TYPEISSEM + if (S_TYPEISSEM (st)) return "semaphore"; +#endif +#ifdef S_TYPEISSHM + if (S_TYPEISSHM (st)) return "shared memory object"; +#endif + + /* other popular file types */ + /* S_ISLNK is impossible with `fstat' and `stat'. */ +#ifdef S_ISSOCK + if (S_ISSOCK (st->st_mode)) return "socket"; +#endif + + return "weird file"; +} + +/* Compare two files (or dirs) with specified names + DIR0/NAME0 and DIR1/NAME1, at level DEPTH in directory recursion. + (if DIR0 is 0, then the name is just NAME0, etc.) + This is self-contained; it opens the files and closes them. + + Value is 0 if files are the same, 1 if different, + 2 if there is a problem opening them. */ + +static int +compare_files (dir0, name0, dir1, name1, depth) + char const *dir0, *dir1; + char const *name0, *name1; + int depth; +{ + struct file_data inf[2]; + register int i; + int val; + int same_files; + int failed = 0; + char *free0 = 0, *free1 = 0; + + /* If this is directory comparison, perhaps we have a file + that exists only in one of the directories. + If so, just print a message to that effect. */ + + if (! ((name0 != 0 && name1 != 0) + || (unidirectional_new_file_flag && name1 != 0) + || entire_new_file_flag)) + { + char const *name = name0 == 0 ? name1 : name0; + char const *dir = name0 == 0 ? dir1 : dir0; + message ("Only in %s: %s\n", dir, name); + /* Return 1 so that diff_dirs will return 1 ("some files differ"). */ + return 1; + } + + bzero (inf, sizeof (inf)); + + /* Mark any nonexistent file with -1 in the desc field. */ + /* Mark unopened files (e.g. directories) with -2. */ + + inf[0].desc = name0 == 0 ? -1 : -2; + inf[1].desc = name1 == 0 ? -1 : -2; + + /* Now record the full name of each file, including nonexistent ones. */ + + if (name0 == 0) + name0 = name1; + if (name1 == 0) + name1 = name0; + + inf[0].name = dir0 == 0 ? name0 : (free0 = dir_file_pathname (dir0, name0)); + inf[1].name = dir1 == 0 ? name1 : (free1 = dir_file_pathname (dir1, name1)); + + /* Stat the files. Record whether they are directories. */ + + for (i = 0; i <= 1; i++) + { + if (inf[i].desc != -1) + { + int stat_result; + + if (i && filename_cmp (inf[i].name, inf[0].name) == 0) + { + inf[i].stat = inf[0].stat; + stat_result = 0; + } + else if (strcmp (inf[i].name, "-") == 0) + { + inf[i].desc = STDIN_FILENO; + stat_result = fstat (STDIN_FILENO, &inf[i].stat); + if (stat_result == 0 && S_ISREG (inf[i].stat.st_mode)) + { + off_t pos = lseek (STDIN_FILENO, (off_t) 0, SEEK_CUR); + if (pos == -1) + stat_result = -1; + else + { + if (pos <= inf[i].stat.st_size) + inf[i].stat.st_size -= pos; + else + inf[i].stat.st_size = 0; + /* Posix.2 4.17.6.1.4 requires current time for stdin. */ + time (&inf[i].stat.st_mtime); + } + } + } + else + stat_result = stat (inf[i].name, &inf[i].stat); + + if (stat_result != 0) + { + perror_with_name (inf[i].name); + failed = 1; + } + else + { + inf[i].dir_p = S_ISDIR (inf[i].stat.st_mode) && inf[i].desc != 0; + if (inf[1 - i].desc == -1) + { + inf[1 - i].dir_p = inf[i].dir_p; + inf[1 - i].stat.st_mode = inf[i].stat.st_mode; + } + } + } + } + + if (! failed && depth == 0 && inf[0].dir_p != inf[1].dir_p) + { + /* If one is a directory, and it was specified in the command line, + use the file in that dir with the other file's basename. */ + + int fnm_arg = inf[0].dir_p; + int dir_arg = 1 - fnm_arg; + char const *fnm = inf[fnm_arg].name; + char const *dir = inf[dir_arg].name; + char const *p = filename_lastdirchar (fnm); + char const *filename = inf[dir_arg].name + = dir_file_pathname (dir, p ? p + 1 : fnm); + + if (strcmp (fnm, "-") == 0) + fatal ("can't compare - to a directory"); + + if (stat (filename, &inf[dir_arg].stat) != 0) + { + perror_with_name (filename); + failed = 1; + } + else + inf[dir_arg].dir_p = S_ISDIR (inf[dir_arg].stat.st_mode); + } + + if (failed) + { + + /* If either file should exist but does not, return 2. */ + + val = 2; + + } + else if ((same_files = inf[0].desc != -1 && inf[1].desc != -1 + && 0 < same_file (&inf[0].stat, &inf[1].stat)) + && no_diff_means_no_output) + { + /* The two named files are actually the same physical file. + We know they are identical without actually reading them. */ + + val = 0; + } + else if (inf[0].dir_p & inf[1].dir_p) + { + if (output_style == OUTPUT_IFDEF) + fatal ("-D option not supported with directories"); + + /* If both are directories, compare the files in them. */ + + if (depth > 0 && !recursive) + { + /* But don't compare dir contents one level down + unless -r was specified. */ + message ("Common subdirectories: %s and %s\n", + inf[0].name, inf[1].name); + val = 0; + } + else + { + val = diff_dirs (inf, compare_files, depth); + } + + } + else if ((inf[0].dir_p | inf[1].dir_p) + || (depth > 0 + && (! S_ISREG (inf[0].stat.st_mode) + || ! S_ISREG (inf[1].stat.st_mode)))) + { + /* Perhaps we have a subdirectory that exists only in one directory. + If so, just print a message to that effect. */ + + if (inf[0].desc == -1 || inf[1].desc == -1) + { + if ((inf[0].dir_p | inf[1].dir_p) + && recursive + && (entire_new_file_flag + || (unidirectional_new_file_flag && inf[0].desc == -1))) + val = diff_dirs (inf, compare_files, depth); + else + { + char const *dir = (inf[0].desc == -1) ? dir1 : dir0; + /* See Posix.2 section 4.17.6.1.1 for this format. */ + message ("Only in %s: %s\n", dir, name0); + val = 1; + } + } + else + { + /* We have two files that are not to be compared. */ + + /* See Posix.2 section 4.17.6.1.1 for this format. */ + message5 ("File %s is a %s while file %s is a %s\n", + inf[0].name, filetype (&inf[0].stat), + inf[1].name, filetype (&inf[1].stat)); + + /* This is a difference. */ + val = 1; + } + } + else if ((no_details_flag & ~ignore_some_changes) + && inf[0].stat.st_size != inf[1].stat.st_size + && (inf[0].desc == -1 || S_ISREG (inf[0].stat.st_mode)) + && (inf[1].desc == -1 || S_ISREG (inf[1].stat.st_mode))) + { + message ("Files %s and %s differ\n", inf[0].name, inf[1].name); + val = 1; + } + else + { + /* Both exist and neither is a directory. */ + + /* Open the files and record their descriptors. */ + + if (inf[0].desc == -2) + if ((inf[0].desc = open (inf[0].name, O_RDONLY, 0)) < 0) + { + perror_with_name (inf[0].name); + failed = 1; + } + if (inf[1].desc == -2) + { + if (same_files) + inf[1].desc = inf[0].desc; + else if ((inf[1].desc = open (inf[1].name, O_RDONLY, 0)) < 0) + { + perror_with_name (inf[1].name); + failed = 1; + } + } + +#if HAVE_SETMODE + if (binary_I_O) + for (i = 0; i <= 1; i++) + if (0 <= inf[i].desc) + setmode (inf[i].desc, O_BINARY); +#endif + + /* Compare the files, if no error was found. */ + + val = failed ? 2 : diff_2_files (inf, depth); + + /* Close the file descriptors. */ + + if (inf[0].desc >= 0 && close (inf[0].desc) != 0) + { + perror_with_name (inf[0].name); + val = 2; + } + if (inf[1].desc >= 0 && inf[0].desc != inf[1].desc + && close (inf[1].desc) != 0) + { + perror_with_name (inf[1].name); + val = 2; + } + } + + /* Now the comparison has been done, if no error prevented it, + and VAL is the value this function will return. */ + + if (val == 0 && !inf[0].dir_p) + { + if (print_file_same_flag) + message ("Files %s and %s are identical\n", + inf[0].name, inf[1].name); + } + else + flush_output (); + + if (free0) + free (free0); + if (free1) + free (free1); + + return val; +} + +/* Initialize status variables and flag variables used in libdiff, + to permit repeated calls to diff_run. */ + +static void +initialize_main (argcp, argvp) + int *argcp; + char ***argvp; +{ + /* These variables really must be reset each time diff_run is called. */ + output_style = OUTPUT_NORMAL; + context = -1; + file_label[0] = NULL; + file_label[1] = NULL; + diff_program_name = (*argvp)[0]; + outfile = NULL; + + /* Reset these also, just for safety's sake. (If one invocation turns + on ignore_case_flag, it must be turned off before diff_run is called + again. But it is possible to make many diffs before encountering + such a problem. */ + recursive = 0; + no_discards = 0; +#if HAVE_SETMODE + binary_I_O = 0; +#endif + no_diff_means_no_output = 0; + always_text_flag = 0; + horizon_lines = 0; + ignore_space_change_flag = 0; + ignore_all_space_flag = 0; + ignore_blank_lines_flag = 0; + ignore_some_line_changes = 0; + ignore_some_changes = 0; + ignore_case_flag = 0; + function_regexp_list = NULL; + ignore_regexp_list = NULL; + no_details_flag = 0; + print_file_same_flag = 0; + tab_align_flag = 0; + tab_expand_flag = 0; + dir_start_file = NULL; + entire_new_file_flag = 0; + unidirectional_new_file_flag = 0; + paginate_flag = 0; + bzero (group_format, sizeof (group_format)); + bzero (line_format, sizeof (line_format)); + sdiff_help_sdiff = 0; + sdiff_left_only = 0; + sdiff_skip_common_lines = 0; + sdiff_half_width = 0; + sdiff_column2_offset = 0; + switch_string = NULL; + heuristic = 0; + bzero (files, sizeof (files)); +} |