1/* Shared definitions for GNU DIFF 2 3 Copyright (C) 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1998, 2001, 4 2002, 2004 Free Software Foundation, Inc. 5 6 This file is part of GNU DIFF. 7 8 GNU DIFF 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 2, or (at your option) 11 any later version. 12 13 GNU DIFF 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. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; see the file COPYING. 20 If not, write to the Free Software Foundation, 21 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ 22 23#include "system.h" 24#include <regex.h> 25#include <stdio.h> 26#include <unlocked-io.h> 27 28/* What kind of changes a hunk contains. */ 29enum changes 30{ 31 /* No changes: lines common to both files. */ 32 UNCHANGED, 33 34 /* Deletes only: lines taken from just the first file. */ 35 OLD, 36 37 /* Inserts only: lines taken from just the second file. */ 38 NEW, 39 40 /* Both deletes and inserts: a hunk containing both old and new lines. */ 41 CHANGED 42}; 43 44/* Variables for command line options */ 45 46#ifndef GDIFF_MAIN 47# define XTERN extern 48#else 49# define XTERN 50#endif 51 52enum output_style 53{ 54 /* No output style specified. */ 55 OUTPUT_UNSPECIFIED, 56 57 /* Default output style. */ 58 OUTPUT_NORMAL, 59 60 /* Output the differences with lines of context before and after (-c). */ 61 OUTPUT_CONTEXT, 62 63 /* Output the differences in a unified context diff format (-u). */ 64 OUTPUT_UNIFIED, 65 66 /* Output the differences as commands suitable for `ed' (-e). */ 67 OUTPUT_ED, 68 69 /* Output the diff as a forward ed script (-f). */ 70 OUTPUT_FORWARD_ED, 71 72 /* Like -f, but output a count of changed lines in each "command" (-n). */ 73 OUTPUT_RCS, 74 75 /* Output merged #ifdef'd file (-D). */ 76 OUTPUT_IFDEF, 77 78 /* Output sdiff style (-y). */ 79 OUTPUT_SDIFF 80}; 81 82/* True for output styles that are robust, 83 i.e. can handle a file that ends in a non-newline. */ 84#define ROBUST_OUTPUT_STYLE(S) ((S) != OUTPUT_ED && (S) != OUTPUT_FORWARD_ED) 85 86XTERN enum output_style output_style; 87 88/* Nonzero if output cannot be generated for identical files. */ 89XTERN bool no_diff_means_no_output; 90 91/* Number of lines of context to show in each set of diffs. 92 This is zero when context is not to be shown. */ 93XTERN lin context; 94 95/* Consider all files as text files (-a). 96 Don't interpret codes over 0177 as implying a "binary file". */ 97XTERN bool text; 98 99/* Number of lines to keep in identical prefix and suffix. */ 100XTERN lin horizon_lines; 101 102/* The significance of white space during comparisons. */ 103XTERN enum 104{ 105 /* All white space is significant (the default). */ 106 IGNORE_NO_WHITE_SPACE, 107 108 /* Ignore changes due to tab expansion (-E). */ 109 IGNORE_TAB_EXPANSION, 110 111 /* Ignore changes in horizontal white space (-b). */ 112 IGNORE_SPACE_CHANGE, 113 114 /* Ignore all horizontal white space (-w). */ 115 IGNORE_ALL_SPACE 116} ignore_white_space; 117 118/* Ignore changes that affect only blank lines (-B). */ 119XTERN bool ignore_blank_lines; 120 121/* Files can be compared byte-by-byte, as if they were binary. 122 This depends on various options. */ 123XTERN bool files_can_be_treated_as_binary; 124 125/* Ignore differences in case of letters (-i). */ 126XTERN bool ignore_case; 127 128/* Ignore differences in case of letters in file names. */ 129XTERN bool ignore_file_name_case; 130 131/* File labels for `-c' output headers (--label). */ 132XTERN char *file_label[2]; 133 134/* Regexp to identify function-header lines (-F). */ 135XTERN struct re_pattern_buffer function_regexp; 136 137/* Ignore changes that affect only lines matching this regexp (-I). */ 138XTERN struct re_pattern_buffer ignore_regexp; 139 140/* Say only whether files differ, not how (-q). */ 141XTERN bool brief; 142 143/* Expand tabs in the output so the text lines up properly 144 despite the characters added to the front of each line (-t). */ 145XTERN bool expand_tabs; 146 147/* Number of columns between tab stops. */ 148XTERN size_t tabsize; 149 150/* Use a tab in the output, rather than a space, before the text of an 151 input line, so as to keep the proper alignment in the input line 152 without changing the characters in it (-T). */ 153XTERN bool initial_tab; 154 155/* Remove trailing carriage returns from input. */ 156XTERN bool strip_trailing_cr; 157 158/* In directory comparison, specify file to start with (-S). 159 This is used for resuming an aborted comparison. 160 All file names less than this name are ignored. */ 161XTERN char const *starting_file; 162 163/* Pipe each file's output through pr (-l). */ 164XTERN bool paginate; 165 166/* Line group formats for unchanged, old, new, and changed groups. */ 167XTERN char const *group_format[CHANGED + 1]; 168 169/* Line formats for unchanged, old, and new lines. */ 170XTERN char const *line_format[NEW + 1]; 171 172/* If using OUTPUT_SDIFF print extra information to help the sdiff filter. */ 173XTERN bool sdiff_merge_assist; 174 175/* Tell OUTPUT_SDIFF to show only the left version of common lines. */ 176XTERN bool left_column; 177 178/* Tell OUTPUT_SDIFF to not show common lines. */ 179XTERN bool suppress_common_lines; 180 181/* The half line width and column 2 offset for OUTPUT_SDIFF. */ 182XTERN size_t sdiff_half_width; 183XTERN size_t sdiff_column2_offset; 184 185/* String containing all the command options diff received, 186 with spaces between and at the beginning but none at the end. 187 If there were no options given, this string is empty. */ 188XTERN char *switch_string; 189 190/* Use heuristics for better speed with large files with a small 191 density of changes. */ 192XTERN bool speed_large_files; 193 194/* Patterns that match file names to be excluded. */ 195XTERN struct exclude *excluded; 196 197/* Don't discard lines. This makes things slower (sometimes much 198 slower) but will find a guaranteed minimal set of changes. */ 199XTERN bool minimal; 200 201/* Name of program the user invoked (for error messages). */ 202XTERN char *program_name; 203 204/* The strftime format to use for time strings. */ 205XTERN char const *time_format; 206 207/* The result of comparison is an "edit script": a chain of `struct change'. 208 Each `struct change' represents one place where some lines are deleted 209 and some are inserted. 210 211 LINE0 and LINE1 are the first affected lines in the two files (origin 0). 212 DELETED is the number of lines deleted here from file 0. 213 INSERTED is the number of lines inserted here in file 1. 214 215 If DELETED is 0 then LINE0 is the number of the line before 216 which the insertion was done; vice versa for INSERTED and LINE1. */ 217 218struct change 219{ 220 struct change *link; /* Previous or next edit command */ 221 lin inserted; /* # lines of file 1 changed here. */ 222 lin deleted; /* # lines of file 0 changed here. */ 223 lin line0; /* Line number of 1st deleted line. */ 224 lin line1; /* Line number of 1st inserted line. */ 225 bool ignore; /* Flag used in context.c. */ 226}; 227 228/* Structures that describe the input files. */ 229 230/* Data on one input file being compared. */ 231 232struct file_data { 233 int desc; /* File descriptor */ 234 char const *name; /* File name */ 235 struct stat stat; /* File status */ 236 237 /* Buffer in which text of file is read. */ 238 word *buffer; 239 240 /* Allocated size of buffer, in bytes. Always a multiple of 241 sizeof *buffer. */ 242 size_t bufsize; 243 244 /* Number of valid bytes now in the buffer. */ 245 size_t buffered; 246 247 /* Array of pointers to lines in the file. */ 248 char const **linbuf; 249 250 /* linbuf_base <= buffered_lines <= valid_lines <= alloc_lines. 251 linebuf[linbuf_base ... buffered_lines - 1] are possibly differing. 252 linebuf[linbuf_base ... valid_lines - 1] contain valid data. 253 linebuf[linbuf_base ... alloc_lines - 1] are allocated. */ 254 lin linbuf_base, buffered_lines, valid_lines, alloc_lines; 255 256 /* Pointer to end of prefix of this file to ignore when hashing. */ 257 char const *prefix_end; 258 259 /* Count of lines in the prefix. 260 There are this many lines in the file before linbuf[0]. */ 261 lin prefix_lines; 262 263 /* Pointer to start of suffix of this file to ignore when hashing. */ 264 char const *suffix_begin; 265 266 /* Vector, indexed by line number, containing an equivalence code for 267 each line. It is this vector that is actually compared with that 268 of another file to generate differences. */ 269 lin *equivs; 270 271 /* Vector, like the previous one except that 272 the elements for discarded lines have been squeezed out. */ 273 lin *undiscarded; 274 275 /* Vector mapping virtual line numbers (not counting discarded lines) 276 to real ones (counting those lines). Both are origin-0. */ 277 lin *realindexes; 278 279 /* Total number of nondiscarded lines. */ 280 lin nondiscarded_lines; 281 282 /* Vector, indexed by real origin-0 line number, 283 containing 1 for a line that is an insertion or a deletion. 284 The results of comparison are stored here. */ 285 char *changed; 286 287 /* 1 if file ends in a line with no final newline. */ 288 bool missing_newline; 289 290 /* 1 if at end of file. */ 291 bool eof; 292 293 /* 1 more than the maximum equivalence value used for this or its 294 sibling file. */ 295 lin equiv_max; 296}; 297 298/* The file buffer, considered as an array of bytes rather than 299 as an array of words. */ 300#define FILE_BUFFER(f) ((char *) (f)->buffer) 301 302/* Data on two input files being compared. */ 303 304struct comparison 305 { 306 struct file_data file[2]; 307 struct comparison const *parent; /* parent, if a recursive comparison */ 308 }; 309 310/* Describe the two files currently being compared. */ 311 312XTERN struct file_data files[2]; 313 314/* Stdio stream to output diffs to. */ 315 316XTERN FILE *outfile; 317 318/* Declare various functions. */ 319 320/* analyze.c */ 321int diff_2_files (struct comparison *); 322 323/* context.c */ 324void print_context_header (struct file_data[], bool); 325void print_context_script (struct change *, bool); 326 327/* dir.c */ 328int diff_dirs (struct comparison const *, int (*) (struct comparison const *, char const *, char const *)); 329 330/* ed.c */ 331void print_ed_script (struct change *); 332void pr_forward_ed_script (struct change *); 333 334/* ifdef.c */ 335void print_ifdef_script (struct change *); 336 337/* io.c */ 338void file_block_read (struct file_data *, size_t); 339bool read_files (struct file_data[], bool); 340 341/* normal.c */ 342void print_normal_script (struct change *); 343 344/* rcs.c */ 345void print_rcs_script (struct change *); 346 347/* side.c */ 348void print_sdiff_script (struct change *); 349 350/* util.c */ 351extern char const change_letter[4]; 352extern char const pr_program[]; 353char *concat (char const *, char const *, char const *); 354char *dir_file_pathname (char const *, char const *); 355bool lines_differ (char const *, char const *); 356lin translate_line_number (struct file_data const *, lin); 357struct change *find_change (struct change *); 358struct change *find_reverse_change (struct change *); 359void *zalloc (size_t); 360enum changes analyze_hunk (struct change *, lin *, lin *, lin *, lin *); 361void begin_output (void); 362void debug_script (struct change *); 363void fatal (char const *) __attribute__((noreturn)); 364void finish_output (void); 365void message (char const *, char const *, char const *); 366void message5 (char const *, char const *, char const *, char const *, char const *); 367void output_1_line (char const *, char const *, char const *, char const *); 368void perror_with_name (char const *); 369void pfatal_with_name (char const *) __attribute__((noreturn)); 370void print_1_line (char const *, char const * const *); 371void print_message_queue (void); 372void print_number_range (char, struct file_data *, lin, lin); 373void print_script (struct change *, struct change * (*) (struct change *), void (*) (struct change *)); 374void setup_output (char const *, char const *, bool); 375void translate_range (struct file_data const *, lin, lin, long int *, long int *); 376