1 /* Shared definitions for GNU DIFF
3 Copyright (C) 1988-1989, 1991-1995, 1998, 2001-2002, 2004, 2009-2013 Free
4 Software Foundation, Inc.
6 This file is part of GNU DIFF.
8 This program is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation, either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include <unlocked-io.h>
26 /* What kind of changes a hunk contains. */
29 /* No changes: lines common to both files. */
32 /* Deletes only: lines taken from just the first file. */
35 /* Inserts only: lines taken from just the second file. */
38 /* Both deletes and inserts: a hunk containing both old and new lines. */
42 /* Variables for command line options */
52 /* No output style specified. */
55 /* Default output style. */
58 /* Output the differences with lines of context before and after (-c). */
61 /* Output the differences in a unified context diff format (-u). */
64 /* Output the differences as commands suitable for 'ed' (-e). */
67 /* Output the diff as a forward ed script (-f). */
70 /* Like -f, but output a count of changed lines in each "command" (-n). */
73 /* Output merged #ifdef'd file (-D). */
76 /* Output sdiff style (-y). */
80 /* True for output styles that are robust,
81 i.e. can handle a file that ends in a non-newline. */
82 #define ROBUST_OUTPUT_STYLE(S) ((S) != OUTPUT_ED && (S) != OUTPUT_FORWARD_ED)
84 XTERN enum output_style output_style;
86 /* Nonzero if output cannot be generated for identical files. */
87 XTERN bool no_diff_means_no_output;
89 /* Number of lines of context to show in each set of diffs.
90 This is zero when context is not to be shown. */
93 /* Consider all files as text files (-a).
94 Don't interpret codes over 0177 as implying a "binary file". */
97 /* Number of lines to keep in identical prefix and suffix. */
98 XTERN lin horizon_lines;
100 /* The significance of white space during comparisons. */
101 enum DIFF_white_space
103 /* All white space is significant (the default). */
104 IGNORE_NO_WHITE_SPACE,
106 /* Ignore changes due to tab expansion (-E). */
107 IGNORE_TAB_EXPANSION,
109 /* Ignore changes in trailing horizontal white space (-Z). */
110 IGNORE_TRAILING_SPACE,
112 /* IGNORE_TAB_EXPANSION and IGNORE_TRAILING_SPACE are a special case
113 because they are independent and can be ORed together, yielding
114 IGNORE_TAB_EXPANSION_AND_TRAILING_SPACE. */
115 IGNORE_TAB_EXPANSION_AND_TRAILING_SPACE,
117 /* Ignore changes in horizontal white space (-b). */
120 /* Ignore all horizontal white space (-w). */
123 XTERN enum DIFF_white_space ignore_white_space;
125 /* Ignore changes that affect only blank lines (-B). */
126 XTERN bool ignore_blank_lines;
128 /* Files can be compared byte-by-byte, as if they were binary.
129 This depends on various options. */
130 XTERN bool files_can_be_treated_as_binary;
132 /* Ignore differences in case of letters (-i). */
133 XTERN bool ignore_case;
135 /* Ignore differences in case of letters in file names. */
136 XTERN bool ignore_file_name_case;
138 /* Act on symbolic links themselves rather than on their target
139 (--no-dereference). */
140 XTERN bool no_dereference_symlinks;
142 /* File labels for '-c' output headers (--label). */
143 XTERN char *file_label[2];
145 /* Regexp to identify function-header lines (-F). */
146 XTERN struct re_pattern_buffer function_regexp;
148 /* Ignore changes that affect only lines matching this regexp (-I). */
149 XTERN struct re_pattern_buffer ignore_regexp;
151 /* Say only whether files differ, not how (-q). */
154 /* Expand tabs in the output so the text lines up properly
155 despite the characters added to the front of each line (-t). */
156 XTERN bool expand_tabs;
158 /* Number of columns between tab stops. */
159 XTERN size_t tabsize;
161 /* Use a tab in the output, rather than a space, before the text of an
162 input line, so as to keep the proper alignment in the input line
163 without changing the characters in it (-T). */
164 XTERN bool initial_tab;
166 /* Do not output an initial space or tab before the text of an empty line. */
167 XTERN bool suppress_blank_empty;
169 /* Remove trailing carriage returns from input. */
170 XTERN bool strip_trailing_cr;
172 /* In directory comparison, specify file to start with (-S).
173 This is used for resuming an aborted comparison.
174 All file names less than this name are ignored. */
175 XTERN char const *starting_file;
177 /* Pipe each file's output through pr (-l). */
180 /* Line group formats for unchanged, old, new, and changed groups. */
181 XTERN char const *group_format[CHANGED + 1];
183 /* Line formats for unchanged, old, and new lines. */
184 XTERN char const *line_format[NEW + 1];
186 /* If using OUTPUT_SDIFF print extra information to help the sdiff filter. */
187 XTERN bool sdiff_merge_assist;
189 /* Tell OUTPUT_SDIFF to show only the left version of common lines. */
190 XTERN bool left_column;
192 /* Tell OUTPUT_SDIFF to not show common lines. */
193 XTERN bool suppress_common_lines;
195 /* The half line width and column 2 offset for OUTPUT_SDIFF. */
196 XTERN size_t sdiff_half_width;
197 XTERN size_t sdiff_column2_offset;
199 /* String containing all the command options diff received,
200 with spaces between and at the beginning but none at the end.
201 If there were no options given, this string is empty. */
202 XTERN char *switch_string;
204 /* Use heuristics for better speed with large files with a small
205 density of changes. */
206 XTERN bool speed_large_files;
208 /* Patterns that match file names to be excluded. */
209 XTERN struct exclude *excluded;
211 /* Don't discard lines. This makes things slower (sometimes much
212 slower) but will find a guaranteed minimal set of changes. */
215 /* The strftime format to use for time strings. */
216 XTERN char const *time_format;
218 /* The result of comparison is an "edit script": a chain of 'struct change'.
219 Each 'struct change' represents one place where some lines are deleted
220 and some are inserted.
222 LINE0 and LINE1 are the first affected lines in the two files (origin 0).
223 DELETED is the number of lines deleted here from file 0.
224 INSERTED is the number of lines inserted here in file 1.
226 If DELETED is 0 then LINE0 is the number of the line before
227 which the insertion was done; vice versa for INSERTED and LINE1. */
231 struct change *link; /* Previous or next edit command */
232 lin inserted; /* # lines of file 1 changed here. */
233 lin deleted; /* # lines of file 0 changed here. */
234 lin line0; /* Line number of 1st deleted line. */
235 lin line1; /* Line number of 1st inserted line. */
236 bool ignore; /* Flag used in context.c. */
239 /* Structures that describe the input files. */
241 /* Data on one input file being compared. */
244 int desc; /* File descriptor */
245 char const *name; /* File name */
246 struct stat stat; /* File status */
248 /* Buffer in which text of file is read. */
251 /* Allocated size of buffer, in bytes. Always a multiple of
255 /* Number of valid bytes now in the buffer. */
258 /* Array of pointers to lines in the file. */
261 /* linbuf_base <= buffered_lines <= valid_lines <= alloc_lines.
262 linebuf[linbuf_base ... buffered_lines - 1] are possibly differing.
263 linebuf[linbuf_base ... valid_lines - 1] contain valid data.
264 linebuf[linbuf_base ... alloc_lines - 1] are allocated. */
265 lin linbuf_base, buffered_lines, valid_lines, alloc_lines;
267 /* Pointer to end of prefix of this file to ignore when hashing. */
268 char const *prefix_end;
270 /* Count of lines in the prefix.
271 There are this many lines in the file before linbuf[0]. */
274 /* Pointer to start of suffix of this file to ignore when hashing. */
275 char const *suffix_begin;
277 /* Vector, indexed by line number, containing an equivalence code for
278 each line. It is this vector that is actually compared with that
279 of another file to generate differences. */
282 /* Vector, like the previous one except that
283 the elements for discarded lines have been squeezed out. */
286 /* Vector mapping virtual line numbers (not counting discarded lines)
287 to real ones (counting those lines). Both are origin-0. */
290 /* Total number of nondiscarded lines. */
291 lin nondiscarded_lines;
293 /* Vector, indexed by real origin-0 line number,
294 containing 1 for a line that is an insertion or a deletion.
295 The results of comparison are stored here. */
298 /* 1 if file ends in a line with no final newline. */
299 bool missing_newline;
301 /* 1 if at end of file. */
304 /* 1 more than the maximum equivalence value used for this or its
309 /* The file buffer, considered as an array of bytes rather than
310 as an array of words. */
311 #define FILE_BUFFER(f) ((char *) (f)->buffer)
313 /* Data on two input files being compared. */
317 struct file_data file[2];
318 struct comparison const *parent; /* parent, if a recursive comparison */
321 /* Describe the two files currently being compared. */
323 XTERN struct file_data files[2];
325 /* Stdio stream to output diffs to. */
329 /* Declare various functions. */
332 extern int diff_2_files (struct comparison *);
335 extern void print_context_header (struct file_data[], char const * const *, bool);
336 extern void print_context_script (struct change *, bool);
339 extern int diff_dirs (struct comparison const *,
340 int (*) (struct comparison const *,
341 char const *, char const *));
342 extern char *find_dir_file_pathname (char const *, char const *);
345 extern void print_ed_script (struct change *);
346 extern void pr_forward_ed_script (struct change *);
349 extern void print_ifdef_script (struct change *);
352 extern void file_block_read (struct file_data *, size_t);
353 extern bool read_files (struct file_data[], bool);
356 extern void print_normal_script (struct change *);
359 extern void print_rcs_script (struct change *);
362 extern void print_sdiff_script (struct change *);
365 extern char const change_letter[4];
366 extern char const pr_program[];
367 extern char *concat (char const *, char const *, char const *);
368 extern bool lines_differ (char const *, char const *) _GL_ATTRIBUTE_PURE;
369 extern lin translate_line_number (struct file_data const *, lin);
370 extern struct change *find_change (struct change *);
371 extern struct change *find_reverse_change (struct change *);
372 extern void *zalloc (size_t);
373 extern enum changes analyze_hunk (struct change *, lin *, lin *, lin *, lin *);
374 extern void begin_output (void);
375 extern void debug_script (struct change *);
376 extern void fatal (char const *) __attribute__((noreturn));
377 extern void finish_output (void);
378 extern void message (char const *, char const *, char const *);
379 extern void message5 (char const *, char const *, char const *,
380 char const *, char const *);
381 extern void output_1_line (char const *, char const *, char const *,
383 extern void perror_with_name (char const *);
384 extern void pfatal_with_name (char const *) __attribute__((noreturn));
385 extern void print_1_line (char const *, char const * const *);
386 extern void print_message_queue (void);
387 extern void print_number_range (char, struct file_data *, lin, lin);
388 extern void print_script (struct change *, struct change * (*) (struct change *),
389 void (*) (struct change *));
390 extern void setup_output (char const *, char const *, bool);
391 extern void translate_range (struct file_data const *, lin, lin,
392 long int *, long int *);