diff options
Diffstat (limited to 'diff/ifdef.c')
| -rw-r--r-- | diff/ifdef.c | 436 |
1 files changed, 436 insertions, 0 deletions
diff --git a/diff/ifdef.c b/diff/ifdef.c new file mode 100644 index 0000000..94fcfb5 --- /dev/null +++ b/diff/ifdef.c @@ -0,0 +1,436 @@ +/* #ifdef-format output routines for GNU DIFF. + Copyright (C) 1989, 1991, 1992, 1993, 1994, 1998 Free Software Foundation, Inc. + +This file is part of GNU DIFF. + +GNU DIFF is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY. No author or distributor +accepts responsibility to anyone for the consequences of using it +or for whether it serves any particular purpose or works at all, +unless he says so in writing. Refer to the GNU DIFF General Public +License for full details. + +Everyone is granted permission to copy, modify and redistribute +GNU DIFF, but only under the conditions described in the +GNU DIFF General Public License. A copy of this license is +supposed to have been given to you along with GNU DIFF so you +can know your rights and responsibilities. It should be in a +file named COPYING. Among other things, the copyright notice +and this notice must be preserved on all copies. */ + + +#include "diff.h" + +struct group +{ + struct file_data const *file; + int from, upto; /* start and limit lines for this group of lines */ +}; + +static char *format_group PARAMS((int, char *, int, struct group const *)); +static char *scan_char_literal PARAMS((char *, int *)); +static char *scan_printf_spec PARAMS((char *)); +static int groups_letter_value PARAMS((struct group const *, int)); +static void format_ifdef PARAMS((char *, int, int, int, int)); +static void print_ifdef_hunk PARAMS((struct change *)); +static void print_ifdef_lines PARAMS((int, char *, struct group const *)); + +static int next_line; + +/* Print the edit-script SCRIPT as a merged #ifdef file. */ + +void +print_ifdef_script (script) + struct change *script; +{ + next_line = - files[0].prefix_lines; + print_script (script, find_change, print_ifdef_hunk); + if (next_line < files[0].valid_lines) + { + begin_output (); + format_ifdef (group_format[UNCHANGED], next_line, files[0].valid_lines, + next_line - files[0].valid_lines + files[1].valid_lines, + files[1].valid_lines); + } +} + +/* Print a hunk of an ifdef diff. + This is a contiguous portion of a complete edit script, + describing changes in consecutive lines. */ + +static void +print_ifdef_hunk (hunk) + struct change *hunk; +{ + int first0, last0, first1, last1, deletes, inserts; + char *format; + + /* Determine range of line numbers involved in each file. */ + analyze_hunk (hunk, &first0, &last0, &first1, &last1, &deletes, &inserts); + if (inserts) + format = deletes ? group_format[CHANGED] : group_format[NEW]; + else if (deletes) + format = group_format[OLD]; + else + return; + + begin_output (); + + /* Print lines up to this change. */ + if (next_line < first0) + format_ifdef (group_format[UNCHANGED], next_line, first0, + next_line - first0 + first1, first1); + + /* Print this change. */ + next_line = last0 + 1; + format_ifdef (format, first0, next_line, first1, last1 + 1); +} + +/* Print a set of lines according to FORMAT. + Lines BEG0 up to END0 are from the first file; + lines BEG1 up to END1 are from the second file. */ + +static void +format_ifdef (format, beg0, end0, beg1, end1) + char *format; + int beg0, end0, beg1, end1; +{ + struct group groups[2]; + + groups[0].file = &files[0]; + groups[0].from = beg0; + groups[0].upto = end0; + groups[1].file = &files[1]; + groups[1].from = beg1; + groups[1].upto = end1; + format_group (1, format, '\0', groups); +} + +/* If DOIT is non-zero, output a set of lines according to FORMAT. + The format ends at the first free instance of ENDCHAR. + Yield the address of the terminating character. + GROUPS specifies which lines to print. + If OUT is zero, do not actually print anything; just scan the format. */ + +static char * +format_group (doit, format, endchar, groups) + int doit; + char *format; + int endchar; + struct group const *groups; +{ + register char c; + register char *f = format; + + while ((c = *f) != endchar && c != 0) + { + f++; + if (c == '%') + { + char *spec = f; + switch ((c = *f++)) + { + case '%': + break; + + case '(': + /* Print if-then-else format e.g. `%(n=1?thenpart:elsepart)'. */ + { + int i, value[2]; + int thendoit, elsedoit; + + for (i = 0; i < 2; i++) + { + unsigned char f0 = f[0]; + if (ISDIGIT (f0)) + { + value[i] = atoi (f); + while (ISDIGIT ((unsigned char) *++f)) + continue; + } + else + { + value[i] = groups_letter_value (groups, f0); + if (value[i] < 0) + goto bad_format; + f++; + } + if (*f++ != "=?"[i]) + goto bad_format; + } + if (value[0] == value[1]) + thendoit = doit, elsedoit = 0; + else + thendoit = 0, elsedoit = doit; + f = format_group (thendoit, f, ':', groups); + if (*f) + { + f = format_group (elsedoit, f + 1, ')', groups); + if (*f) + f++; + } + } + continue; + + case '<': + /* Print lines deleted from first file. */ + print_ifdef_lines (doit, line_format[OLD], &groups[0]); + continue; + + case '=': + /* Print common lines. */ + print_ifdef_lines (doit, line_format[UNCHANGED], &groups[0]); + continue; + + case '>': + /* Print lines inserted from second file. */ + print_ifdef_lines (doit, line_format[NEW], &groups[1]); + continue; + + default: + { + int value; + char *speclim; + + f = scan_printf_spec (spec); + if (!f) + goto bad_format; + speclim = f; + c = *f++; + switch (c) + { + case '\'': + f = scan_char_literal (f, &value); + if (!f) + goto bad_format; + break; + + default: + value = groups_letter_value (groups, c); + if (value < 0) + goto bad_format; + break; + } + if (doit) + { + /* Temporarily replace e.g. "%3dnx" with "%3d\0x". */ + *speclim = 0; + printf_output (spec - 1, value); + /* Undo the temporary replacement. */ + *speclim = c; + } + } + continue; + + bad_format: + c = '%'; + f = spec; + break; + } + } + if (doit) + { + /* Don't take the address of a register variable. */ + char cc = c; + write_output (&cc, 1); + } + } + return f; +} + +/* For the line group pair G, return the number corresponding to LETTER. + Return -1 if LETTER is not a group format letter. */ +static int +groups_letter_value (g, letter) + struct group const *g; + int letter; +{ + if (ISUPPER (letter)) + { + g++; + letter = tolower (letter); + } + switch (letter) + { + case 'e': return translate_line_number (g->file, g->from) - 1; + case 'f': return translate_line_number (g->file, g->from); + case 'l': return translate_line_number (g->file, g->upto) - 1; + case 'm': return translate_line_number (g->file, g->upto); + case 'n': return g->upto - g->from; + default: return -1; + } +} + +/* Output using FORMAT to print the line group GROUP. + But do nothing if DOIT is zero. */ +static void +print_ifdef_lines (doit, format, group) + int doit; + char *format; + struct group const *group; +{ + struct file_data const *file = group->file; + char const * const *linbuf = file->linbuf; + int from = group->from, upto = group->upto; + + if (!doit) + return; + + /* If possible, use a single fwrite; it's faster. */ + if (!tab_expand_flag && format[0] == '%') + { + if (format[1] == 'l' && format[2] == '\n' && !format[3]) + { + write_output (linbuf[from], + (linbuf[upto] + (linbuf[upto][-1] != '\n') + - linbuf[from])); + return; + } + if (format[1] == 'L' && !format[2]) + { + write_output (linbuf[from], + linbuf[upto] - linbuf[from]); + return; + } + } + + for (; from < upto; from++) + { + register char c; + register char *f = format; + char cc; + + while ((c = *f++) != 0) + { + if (c == '%') + { + char *spec = f; + switch ((c = *f++)) + { + case '%': + break; + + case 'l': + output_1_line (linbuf[from], + linbuf[from + 1] + - (linbuf[from + 1][-1] == '\n'), 0, 0); + continue; + + case 'L': + output_1_line (linbuf[from], linbuf[from + 1], 0, 0); + continue; + + default: + { + int value; + char *speclim; + + f = scan_printf_spec (spec); + if (!f) + goto bad_format; + speclim = f; + c = *f++; + switch (c) + { + case '\'': + f = scan_char_literal (f, &value); + if (!f) + goto bad_format; + break; + + case 'n': + value = translate_line_number (file, from); + break; + + default: + goto bad_format; + } + /* Temporarily replace e.g. "%3dnx" with "%3d\0x". */ + *speclim = 0; + printf_output (spec - 1, value); + /* Undo the temporary replacement. */ + *speclim = c; + } + continue; + + bad_format: + c = '%'; + f = spec; + break; + } + } + + /* Don't take the address of a register variable. */ + cc = c; + write_output (&cc, 1); + } + } +} + +/* Scan the character literal represented in the string LIT; LIT points just + after the initial apostrophe. Put the literal's value into *INTPTR. + Yield the address of the first character after the closing apostrophe, + or zero if the literal is ill-formed. */ +static char * +scan_char_literal (lit, intptr) + char *lit; + int *intptr; +{ + register char *p = lit; + int value, digits; + char c = *p++; + + switch (c) + { + case 0: + case '\'': + return 0; + + case '\\': + value = 0; + while ((c = *p++) != '\'') + { + unsigned digit = c - '0'; + if (8 <= digit) + return 0; + value = 8 * value + digit; + } + digits = p - lit - 2; + if (! (1 <= digits && digits <= 3)) + return 0; + break; + + default: + value = c; + if (*p++ != '\'') + return 0; + break; + } + *intptr = value; + return p; +} + +/* Scan optional printf-style SPEC of the form `-*[0-9]*(.[0-9]*)?[cdoxX]'. + Return the address of the character following SPEC, or zero if failure. */ +static char * +scan_printf_spec (spec) + register char *spec; +{ + register unsigned char c; + + while ((c = *spec++) == '-') + continue; + while (ISDIGIT (c)) + c = *spec++; + if (c == '.') + while (ISDIGIT (c = *spec++)) + continue; + switch (c) + { + case 'c': case 'd': case 'o': case 'x': case 'X': + return spec; + + default: + return 0; + } +} |