xref: /plan9/sys/src/ape/cmd/diff/diff.h (revision 0b459c2cb92b7c9d88818e9a2f72e678e5bc4553)
1 /* Shared definitions for GNU DIFF
2    Copyright (C) 1988, 89, 91, 92, 93 Free Software Foundation, Inc.
3 
4 This file is part of GNU DIFF.
5 
6 GNU DIFF is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
9 any later version.
10 
11 GNU DIFF is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 GNU General Public License for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GNU DIFF; see the file COPYING.  If not, write to
18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
19 
20 #include "system.h"
21 #include <stdio.h>
22 #ifdef __FreeBSD__
23 #include <gnuregex.h>
24 #else
25 #include "regex.h"
26 #endif
27 
28 #define TAB_WIDTH 8
29 
30 /* Variables for command line options */
31 
32 #ifndef GDIFF_MAIN
33 #define EXTERN extern
34 #else
35 #define EXTERN
36 #endif
37 
38 enum output_style {
39   /* Default output style.  */
40   OUTPUT_NORMAL,
41   /* Output the differences with lines of context before and after (-c).  */
42   OUTPUT_CONTEXT,
43   /* Output the differences in a unified context diff format (-u). */
44   OUTPUT_UNIFIED,
45   /* Output the differences as commands suitable for `ed' (-e).  */
46   OUTPUT_ED,
47   /* Output the diff as a forward ed script (-f).  */
48   OUTPUT_FORWARD_ED,
49   /* Like -f, but output a count of changed lines in each "command" (-n). */
50   OUTPUT_RCS,
51   /* Output merged #ifdef'd file (-D).  */
52   OUTPUT_IFDEF,
53   /* Output sdiff style (-y).  */
54   OUTPUT_SDIFF
55 };
56 
57 /* True for output styles that are robust,
58    i.e. can handle a file that ends in a non-newline.  */
59 #define ROBUST_OUTPUT_STYLE(S) ((S) != OUTPUT_ED && (S) != OUTPUT_FORWARD_ED)
60 
61 EXTERN enum output_style output_style;
62 
63 /* Nonzero if output cannot be generated for identical files.  */
64 EXTERN int no_diff_means_no_output;
65 
66 /* Number of lines of context to show in each set of diffs.
67    This is zero when context is not to be shown.  */
68 EXTERN int      context;
69 
70 /* Consider all files as text files (-a).
71    Don't interpret codes over 0177 as implying a "binary file".  */
72 EXTERN int	always_text_flag;
73 
74 /* Number of lines to keep in identical prefix and suffix.  */
75 EXTERN int      horizon_lines;
76 
77 /* Ignore changes in horizontal white space (-b).  */
78 EXTERN int      ignore_space_change_flag;
79 
80 /* Ignore all horizontal white space (-w).  */
81 EXTERN int      ignore_all_space_flag;
82 
83 /* Ignore changes that affect only blank lines (-B).  */
84 EXTERN int      ignore_blank_lines_flag;
85 
86 /* 1 if lines may match even if their contents do not match exactly.
87    This depends on various options.  */
88 EXTERN int      ignore_some_line_changes;
89 
90 /* 1 if files may match even if their contents are not byte-for-byte identical.
91    This depends on various options.  */
92 EXTERN int      ignore_some_changes;
93 
94 /* Ignore differences in case of letters (-i).  */
95 EXTERN int      ignore_case_flag;
96 
97 /* File labels for `-c' output headers (-L).  */
98 EXTERN char *file_label[2];
99 
100 struct regexp_list
101 {
102   struct re_pattern_buffer buf;
103   struct regexp_list *next;
104 };
105 
106 /* Regexp to identify function-header lines (-F).  */
107 EXTERN struct regexp_list *function_regexp_list;
108 
109 /* Ignore changes that affect only lines matching this regexp (-I).  */
110 EXTERN struct regexp_list *ignore_regexp_list;
111 
112 /* Say only whether files differ, not how (-q).  */
113 EXTERN int 	no_details_flag;
114 
115 /* Report files compared that match (-s).
116    Normally nothing is output when that happens.  */
117 EXTERN int      print_file_same_flag;
118 
119 /* Output the differences with exactly 8 columns added to each line
120    so that any tabs in the text line up properly (-T).  */
121 EXTERN int	tab_align_flag;
122 
123 /* Expand tabs in the output so the text lines up properly
124    despite the characters added to the front of each line (-t).  */
125 EXTERN int	tab_expand_flag;
126 
127 /* In directory comparison, specify file to start with (-S).
128    All file names less than this name are ignored.  */
129 EXTERN char	*dir_start_file;
130 
131 /* If a file is new (appears in only one dir)
132    include its entire contents (-N).
133    Then `patch' would create the file with appropriate contents.  */
134 EXTERN int	entire_new_file_flag;
135 
136 /* If a file is new (appears in only the second dir)
137    include its entire contents (-P).
138    Then `patch' would create the file with appropriate contents.  */
139 EXTERN int	unidirectional_new_file_flag;
140 
141 /* Pipe each file's output through pr (-l).  */
142 EXTERN int	paginate_flag;
143 
144 enum line_class {
145   /* Lines taken from just the first file.  */
146   OLD,
147   /* Lines taken from just the second file.  */
148   NEW,
149   /* Lines common to both files.  */
150   UNCHANGED,
151   /* A hunk containing both old and new lines (line groups only).  */
152   CHANGED
153 };
154 
155 /* Line group formats for old, new, unchanged, and changed groups.  */
156 EXTERN char *group_format[CHANGED + 1];
157 
158 /* Line formats for old, new, and unchanged lines.  */
159 EXTERN char *line_format[UNCHANGED + 1];
160 
161 /* If using OUTPUT_SDIFF print extra information to help the sdiff filter. */
162 EXTERN int sdiff_help_sdiff;
163 
164 /* Tell OUTPUT_SDIFF to show only the left version of common lines. */
165 EXTERN int sdiff_left_only;
166 
167 /* Tell OUTPUT_SDIFF to not show common lines. */
168 EXTERN int sdiff_skip_common_lines;
169 
170 /* The half line width and column 2 offset for OUTPUT_SDIFF.  */
171 EXTERN unsigned sdiff_half_width;
172 EXTERN unsigned sdiff_column2_offset;
173 
174 /* String containing all the command options diff received,
175    with spaces between and at the beginning but none at the end.
176    If there were no options given, this string is empty.  */
177 EXTERN char *	switch_string;
178 
179 /* Nonzero means use heuristics for better speed.  */
180 EXTERN int	heuristic;
181 
182 /* Name of program the user invoked (for error messages).  */
183 EXTERN char *program_name;
184 
185 /* The result of comparison is an "edit script": a chain of `struct change'.
186    Each `struct change' represents one place where some lines are deleted
187    and some are inserted.
188 
189    LINE0 and LINE1 are the first affected lines in the two files (origin 0).
190    DELETED is the number of lines deleted here from file 0.
191    INSERTED is the number of lines inserted here in file 1.
192 
193    If DELETED is 0 then LINE0 is the number of the line before
194    which the insertion was done; vice versa for INSERTED and LINE1.  */
195 
196 struct change
197 {
198   struct change *link;		/* Previous or next edit command  */
199   int inserted;			/* # lines of file 1 changed here.  */
200   int deleted;			/* # lines of file 0 changed here.  */
201   int line0;			/* Line number of 1st deleted line.  */
202   int line1;			/* Line number of 1st inserted line.  */
203   char ignore;			/* Flag used in context.c */
204 };
205 
206 /* Structures that describe the input files.  */
207 
208 /* Data on one input file being compared.  */
209 
210 struct file_data {
211     int             desc;	/* File descriptor  */
212     char const      *name;	/* File name  */
213     struct stat     stat;	/* File status from fstat()  */
214     int             dir_p;	/* nonzero if file is a directory  */
215 
216     /* Buffer in which text of file is read.  */
217     char *	    buffer;
218     /* Allocated size of buffer.  */
219     size_t	    bufsize;
220     /* Number of valid characters now in the buffer. */
221     size_t	    buffered_chars;
222 
223     /* Array of pointers to lines in the file.  */
224     char const **linbuf;
225 
226     /* linbuf_base <= buffered_lines <= valid_lines <= alloc_lines.
227        linebuf[linbuf_base ... buffered_lines - 1] are possibly differing.
228        linebuf[linbuf_base ... valid_lines - 1] contain valid data.
229        linebuf[linbuf_base ... alloc_lines - 1] are allocated.  */
230     int linbuf_base, buffered_lines, valid_lines, alloc_lines;
231 
232     /* Pointer to end of prefix of this file to ignore when hashing. */
233     char const *prefix_end;
234 
235     /* Count of lines in the prefix.
236        There are this many lines in the file before linbuf[0].  */
237     int prefix_lines;
238 
239     /* Pointer to start of suffix of this file to ignore when hashing. */
240     char const *suffix_begin;
241 
242     /* Vector, indexed by line number, containing an equivalence code for
243        each line.  It is this vector that is actually compared with that
244        of another file to generate differences. */
245     int		   *equivs;
246 
247     /* Vector, like the previous one except that
248        the elements for discarded lines have been squeezed out.  */
249     int		   *undiscarded;
250 
251     /* Vector mapping virtual line numbers (not counting discarded lines)
252        to real ones (counting those lines).  Both are origin-0.  */
253     int		   *realindexes;
254 
255     /* Total number of nondiscarded lines. */
256     int		    nondiscarded_lines;
257 
258     /* Vector, indexed by real origin-0 line number,
259        containing 1 for a line that is an insertion or a deletion.
260        The results of comparison are stored here.  */
261     char	   *changed_flag;
262 
263     /* 1 if file ends in a line with no final newline. */
264     int		    missing_newline;
265 
266     /* 1 more than the maximum equivalence value used for this or its
267        sibling file. */
268     int equiv_max;
269 };
270 
271 /* Describe the two files currently being compared.  */
272 
273 EXTERN struct file_data files[2];
274 
275 /* Stdio stream to output diffs to.  */
276 
277 EXTERN FILE *outfile;
278 
279 /* Declare various functions.  */
280 
281 /* analyze.c */
282 int diff_2_files PARAMS((struct file_data[], int));
283 
284 /* context.c */
285 void print_context_header PARAMS((struct file_data[], int));
286 void print_context_script PARAMS((struct change *, int));
287 
288 /* diff.c */
289 int excluded_filename PARAMS((char const *));
290 
291 /* dir.c */
292 int diff_dirs PARAMS((struct file_data const[], int (*) PARAMS((char const *, char const *, char const *, char const *, int)), int));
293 
294 /* ed.c */
295 void print_ed_script PARAMS((struct change *));
296 void pr_forward_ed_script PARAMS((struct change *));
297 
298 /* ifdef.c */
299 void print_ifdef_script PARAMS((struct change *));
300 
301 /* io.c */
302 int read_files PARAMS((struct file_data[], int));
303 int sip PARAMS((struct file_data *, int));
304 void slurp PARAMS((struct file_data *));
305 
306 /* normal.c */
307 void print_normal_script PARAMS((struct change *));
308 
309 /* rcs.c */
310 void print_rcs_script PARAMS((struct change *));
311 
312 /* side.c */
313 void print_sdiff_script PARAMS((struct change *));
314 
315 /* util.c */
316 VOID *xmalloc PARAMS((size_t));
317 VOID *xrealloc PARAMS((VOID *, size_t));
318 char *concat PARAMS((char const *, char const *, char const *));
319 char *dir_file_pathname PARAMS((char const *, char const *));
320 int change_letter PARAMS((int, int));
321 int line_cmp PARAMS((char const *, char const *));
322 int translate_line_number PARAMS((struct file_data const *, int));
323 struct change *find_change PARAMS((struct change *));
324 struct change *find_reverse_change PARAMS((struct change *));
325 void analyze_hunk PARAMS((struct change *, int *, int *, int *, int *, int *, int *));
326 void begin_output PARAMS((void));
327 void debug_script PARAMS((struct change *));
328 void error PARAMS((char const *, char const *, char const *));
329 void fatal PARAMS((char const *));
330 void finish_output PARAMS((void));
331 void message PARAMS((char const *, char const *, char const *));
332 void message5 PARAMS((char const *, char const *, char const *, char const *, char const *));
333 void output_1_line PARAMS((char const *, char const *, char const *, char const *));
334 void perror_with_name PARAMS((char const *));
335 void pfatal_with_name PARAMS((char const *));
336 void print_1_line PARAMS((char const *, char const * const *));
337 void print_message_queue PARAMS((void));
338 void print_number_range PARAMS((int, struct file_data *, int, int));
339 void print_script PARAMS((struct change *, struct change * (*) PARAMS((struct change *)), void (*) PARAMS((struct change *))));
340 void setup_output PARAMS((char const *, char const *, int));
341 void translate_range PARAMS((struct file_data const *, int, int, int *, int *));
342 
343 /* version.c */
344 extern char const version_string[];
345