1 /* Shared definitions for GNU DIFF 2 3 Copyright (C) 1988-1989, 1991-1995, 1998, 2001-2002, 2004, 2009-2013, 4 2015-2018 Free Software Foundation, Inc. 5 6 This file is part of GNU DIFF. 7 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. 12 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. 17 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/>. */ 20 21 #include "system.h" 22 #include <regex.h> 23 #include <stdio.h> 24 #include <unlocked-io.h> 25 26 /* What kind of changes a hunk contains. */ 27 enum changes 28 { 29 /* No changes: lines common to both files. */ 30 UNCHANGED, 31 32 /* Deletes only: lines taken from just the first file. */ 33 OLD, 34 35 /* Inserts only: lines taken from just the second file. */ 36 NEW, 37 38 /* Both deletes and inserts: a hunk containing both old and new lines. */ 39 CHANGED 40 }; 41 42 /* When colors should be used in the output. */ 43 enum colors_style 44 { 45 /* Never output colors. */ 46 NEVER, 47 48 /* Output colors if the output is a terminal. */ 49 AUTO, 50 51 /* Always output colors. */ 52 ALWAYS, 53 }; 54 55 /* Variables for command line options */ 56 57 #ifndef GDIFF_MAIN 58 # define XTERN extern 59 #else 60 # define XTERN 61 #endif 62 63 enum output_style 64 { 65 /* No output style specified. */ 66 OUTPUT_UNSPECIFIED, 67 68 /* Default output style. */ 69 OUTPUT_NORMAL, 70 71 /* Output the differences with lines of context before and after (-c). */ 72 OUTPUT_CONTEXT, 73 74 /* Output the differences in a unified context diff format (-u). */ 75 OUTPUT_UNIFIED, 76 77 /* Output the differences as commands suitable for 'ed' (-e). */ 78 OUTPUT_ED, 79 80 /* Output the diff as a forward ed script (-f). */ 81 OUTPUT_FORWARD_ED, 82 83 /* Like -f, but output a count of changed lines in each "command" (-n). */ 84 OUTPUT_RCS, 85 86 /* Output merged #ifdef'd file (-D). */ 87 OUTPUT_IFDEF, 88 89 /* Output sdiff style (-y). */ 90 OUTPUT_SDIFF 91 }; 92 93 /* True for output styles that are robust, 94 i.e. can handle a file that ends in a non-newline. */ 95 #define ROBUST_OUTPUT_STYLE(S) ((S) != OUTPUT_ED && (S) != OUTPUT_FORWARD_ED) 96 97 XTERN enum output_style output_style; 98 99 /* Define the current color context used to print a line. */ 100 XTERN enum colors_style colors_style; 101 102 /* Nonzero if output cannot be generated for identical files. */ 103 XTERN bool no_diff_means_no_output; 104 105 /* Number of lines of context to show in each set of diffs. 106 This is zero when context is not to be shown. */ 107 XTERN lin context; 108 109 /* Consider all files as text files (-a). 110 Don't interpret codes over 0177 as implying a "binary file". */ 111 XTERN bool text; 112 113 /* Number of lines to keep in identical prefix and suffix. */ 114 XTERN lin horizon_lines; 115 116 /* The significance of white space during comparisons. */ 117 enum DIFF_white_space 118 { 119 /* All white space is significant (the default). */ 120 IGNORE_NO_WHITE_SPACE, 121 122 /* Ignore changes due to tab expansion (-E). */ 123 IGNORE_TAB_EXPANSION, 124 125 /* Ignore changes in trailing horizontal white space (-Z). */ 126 IGNORE_TRAILING_SPACE, 127 128 /* IGNORE_TAB_EXPANSION and IGNORE_TRAILING_SPACE are a special case 129 because they are independent and can be ORed together, yielding 130 IGNORE_TAB_EXPANSION_AND_TRAILING_SPACE. */ 131 IGNORE_TAB_EXPANSION_AND_TRAILING_SPACE, 132 133 /* Ignore changes in horizontal white space (-b). */ 134 IGNORE_SPACE_CHANGE, 135 136 /* Ignore all horizontal white space (-w). */ 137 IGNORE_ALL_SPACE 138 }; 139 XTERN enum DIFF_white_space ignore_white_space; 140 141 /* Ignore changes that affect only blank lines (-B). */ 142 XTERN bool ignore_blank_lines; 143 144 /* Files can be compared byte-by-byte, as if they were binary. 145 This depends on various options. */ 146 XTERN bool files_can_be_treated_as_binary; 147 148 /* Ignore differences in case of letters (-i). */ 149 XTERN bool ignore_case; 150 151 /* Ignore differences in case of letters in file names. */ 152 XTERN bool ignore_file_name_case; 153 154 /* Act on symbolic links themselves rather than on their target 155 (--no-dereference). */ 156 XTERN bool no_dereference_symlinks; 157 158 /* File labels for '-c' output headers (--label). */ 159 XTERN char *file_label[2]; 160 161 /* Regexp to identify function-header lines (-F). */ 162 XTERN struct re_pattern_buffer function_regexp; 163 164 /* Ignore changes that affect only lines matching this regexp (-I). */ 165 XTERN struct re_pattern_buffer ignore_regexp; 166 167 /* Say only whether files differ, not how (-q). */ 168 XTERN bool brief; 169 170 /* Expand tabs in the output so the text lines up properly 171 despite the characters added to the front of each line (-t). */ 172 XTERN bool expand_tabs; 173 174 /* Number of columns between tab stops. */ 175 XTERN size_t tabsize; 176 177 /* Use a tab in the output, rather than a space, before the text of an 178 input line, so as to keep the proper alignment in the input line 179 without changing the characters in it (-T). */ 180 XTERN bool initial_tab; 181 182 /* Do not output an initial space or tab before the text of an empty line. */ 183 XTERN bool suppress_blank_empty; 184 185 /* Remove trailing carriage returns from input. */ 186 XTERN bool strip_trailing_cr; 187 188 /* In directory comparison, specify file to start with (-S). 189 This is used for resuming an aborted comparison. 190 All file names less than this name are ignored. */ 191 XTERN char const *starting_file; 192 193 /* Pipe each file's output through pr (-l). */ 194 XTERN bool paginate; 195 196 /* Line group formats for unchanged, old, new, and changed groups. */ 197 XTERN char const *group_format[CHANGED + 1]; 198 199 /* Line formats for unchanged, old, and new lines. */ 200 XTERN char const *line_format[NEW + 1]; 201 202 /* If using OUTPUT_SDIFF print extra information to help the sdiff filter. */ 203 XTERN bool sdiff_merge_assist; 204 205 /* Tell OUTPUT_SDIFF to show only the left version of common lines. */ 206 XTERN bool left_column; 207 208 /* Tell OUTPUT_SDIFF to not show common lines. */ 209 XTERN bool suppress_common_lines; 210 211 /* The half line width and column 2 offset for OUTPUT_SDIFF. */ 212 XTERN size_t sdiff_half_width; 213 XTERN size_t sdiff_column2_offset; 214 215 /* String containing all the command options diff received, 216 with spaces between and at the beginning but none at the end. 217 If there were no options given, this string is empty. */ 218 XTERN char *switch_string; 219 220 /* Use heuristics for better speed with large files with a small 221 density of changes. */ 222 XTERN bool speed_large_files; 223 224 /* Patterns that match file names to be excluded. */ 225 XTERN struct exclude *excluded; 226 227 /* Don't discard lines. This makes things slower (sometimes much 228 slower) but will find a guaranteed minimal set of changes. */ 229 XTERN bool minimal; 230 231 /* The strftime format to use for time strings. */ 232 XTERN char const *time_format; 233 234 /* The result of comparison is an "edit script": a chain of 'struct change'. 235 Each 'struct change' represents one place where some lines are deleted 236 and some are inserted. 237 238 LINE0 and LINE1 are the first affected lines in the two files (origin 0). 239 DELETED is the number of lines deleted here from file 0. 240 INSERTED is the number of lines inserted here in file 1. 241 242 If DELETED is 0 then LINE0 is the number of the line before 243 which the insertion was done; vice versa for INSERTED and LINE1. */ 244 245 struct change 246 { 247 struct change *link; /* Previous or next edit command */ 248 lin inserted; /* # lines of file 1 changed here. */ 249 lin deleted; /* # lines of file 0 changed here. */ 250 lin line0; /* Line number of 1st deleted line. */ 251 lin line1; /* Line number of 1st inserted line. */ 252 bool ignore; /* Flag used in context.c. */ 253 }; 254 255 /* Structures that describe the input files. */ 256 257 /* Data on one input file being compared. */ 258 259 struct file_data { 260 int desc; /* File descriptor */ 261 char const *name; /* File name */ 262 struct stat stat; /* File status */ 263 264 /* Buffer in which text of file is read. */ 265 word *buffer; 266 267 /* Allocated size of buffer, in bytes. Always a multiple of 268 sizeof *buffer. */ 269 size_t bufsize; 270 271 /* Number of valid bytes now in the buffer. */ 272 size_t buffered; 273 274 /* Array of pointers to lines in the file. */ 275 char const **linbuf; 276 277 /* linbuf_base <= buffered_lines <= valid_lines <= alloc_lines. 278 linebuf[linbuf_base ... buffered_lines - 1] are possibly differing. 279 linebuf[linbuf_base ... valid_lines - 1] contain valid data. 280 linebuf[linbuf_base ... alloc_lines - 1] are allocated. */ 281 lin linbuf_base, buffered_lines, valid_lines, alloc_lines; 282 283 /* Pointer to end of prefix of this file to ignore when hashing. */ 284 char const *prefix_end; 285 286 /* Count of lines in the prefix. 287 There are this many lines in the file before linbuf[0]. */ 288 lin prefix_lines; 289 290 /* Pointer to start of suffix of this file to ignore when hashing. */ 291 char const *suffix_begin; 292 293 /* Vector, indexed by line number, containing an equivalence code for 294 each line. It is this vector that is actually compared with that 295 of another file to generate differences. */ 296 lin *equivs; 297 298 /* Vector, like the previous one except that 299 the elements for discarded lines have been squeezed out. */ 300 lin *undiscarded; 301 302 /* Vector mapping virtual line numbers (not counting discarded lines) 303 to real ones (counting those lines). Both are origin-0. */ 304 lin *realindexes; 305 306 /* Total number of nondiscarded lines. */ 307 lin nondiscarded_lines; 308 309 /* Vector, indexed by real origin-0 line number, 310 containing 1 for a line that is an insertion or a deletion. 311 The results of comparison are stored here. */ 312 char *changed; 313 314 /* 1 if file ends in a line with no final newline. */ 315 bool missing_newline; 316 317 /* 1 if at end of file. */ 318 bool eof; 319 320 /* 1 more than the maximum equivalence value used for this or its 321 sibling file. */ 322 lin equiv_max; 323 }; 324 325 /* The file buffer, considered as an array of bytes rather than 326 as an array of words. */ 327 #define FILE_BUFFER(f) ((char *) (f)->buffer) 328 329 /* Data on two input files being compared. */ 330 331 struct comparison 332 { 333 struct file_data file[2]; 334 struct comparison const *parent; /* parent, if a recursive comparison */ 335 }; 336 337 /* Describe the two files currently being compared. */ 338 339 XTERN struct file_data files[2]; 340 341 /* Stdio stream to output diffs to. */ 342 343 XTERN FILE *outfile; 344 345 /* Declare various functions. */ 346 347 /* analyze.c */ 348 extern int diff_2_files (struct comparison *); 349 350 /* context.c */ 351 extern void print_context_header (struct file_data[], char const * const *, bool); 352 extern void print_context_script (struct change *, bool); 353 354 /* dir.c */ 355 extern int diff_dirs (struct comparison const *, 356 int (*) (struct comparison const *, 357 char const *, char const *)); 358 extern char *find_dir_file_pathname (char const *, char const *); 359 360 /* ed.c */ 361 extern void print_ed_script (struct change *); 362 extern void pr_forward_ed_script (struct change *); 363 364 /* ifdef.c */ 365 extern void print_ifdef_script (struct change *); 366 367 /* io.c */ 368 extern void file_block_read (struct file_data *, size_t); 369 extern bool read_files (struct file_data[], bool); 370 371 /* normal.c */ 372 extern void print_normal_script (struct change *); 373 374 /* rcs.c */ 375 extern void print_rcs_script (struct change *); 376 377 /* side.c */ 378 extern void print_sdiff_script (struct change *); 379 380 /* util.c */ 381 extern char const change_letter[4]; 382 extern char const pr_program[]; 383 extern char *concat (char const *, char const *, char const *); 384 extern bool lines_differ (char const *, char const *) _GL_ATTRIBUTE_PURE; 385 extern lin translate_line_number (struct file_data const *, lin); 386 extern struct change *find_change (struct change *); 387 extern struct change *find_reverse_change (struct change *); 388 extern void *zalloc (size_t); 389 extern enum changes analyze_hunk (struct change *, lin *, lin *, lin *, lin *); 390 extern void begin_output (void); 391 extern void debug_script (struct change *); 392 extern void fatal (char const *) __attribute__((noreturn)); 393 extern void finish_output (void); 394 extern void message (char const *, char const *, char const *); 395 extern void message5 (char const *, char const *, char const *, 396 char const *, char const *); 397 extern void output_1_line (char const *, char const *, char const *, 398 char const *); 399 extern void perror_with_name (char const *); 400 extern void pfatal_with_name (char const *) __attribute__((noreturn)); 401 extern void print_1_line (char const *, char const * const *); 402 extern void print_1_line_nl (char const *, char const * const *, bool); 403 extern void print_message_queue (void); 404 extern void print_number_range (char, struct file_data *, lin, lin); 405 extern void print_script (struct change *, struct change * (*) (struct change *), 406 void (*) (struct change *)); 407 extern void setup_output (char const *, char const *, bool); 408 extern void translate_range (struct file_data const *, lin, lin, 409 printint *, printint *); 410 411 enum color_context 412 { 413 HEADER_CONTEXT, 414 ADD_CONTEXT, 415 DELETE_CONTEXT, 416 RESET_CONTEXT, 417 LINE_NUMBER_CONTEXT, 418 }; 419 420 XTERN bool presume_output_tty; 421 422 extern void set_color_context (enum color_context color_context); 423 extern void set_color_palette (char const *palette); 424