1 /* sdiff-format output routines for GNU DIFF. 2 3 Copyright (C) 1991-1993, 1998, 2001-2002, 2004, 2009-2013 Free Software 4 Foundation, Inc. 5 6 This file is part of GNU DIFF. 7 8 GNU DIFF is distributed in the hope that it will be useful, 9 but WITHOUT ANY WARRANTY. No author or distributor 10 accepts responsibility to anyone for the consequences of using it 11 or for whether it serves any particular purpose or works at all, 12 unless he says so in writing. Refer to the GNU General Public 13 License for full details. 14 15 Everyone is granted permission to copy, modify and redistribute 16 GNU DIFF, but only under the conditions described in the 17 GNU General Public License. A copy of this license is 18 supposed to have been given to you along with GNU DIFF so you 19 can know your rights and responsibilities. It should be in a 20 file named COPYING. Among other things, the copyright notice 21 and this notice must be preserved on all copies. */ 22 23 #include "diff.h" 24 25 #include <wchar.h> 26 #include <gnuwidechar.h> 27 28 static void print_sdiff_common_lines (lin, lin); 29 static void print_sdiff_hunk (struct change *); 30 31 /* Next line number to be printed in the two input files. */ 32 static lin next0, next1; 33 34 /* Print the edit-script SCRIPT as a sdiff style output. */ 35 36 void 37 print_sdiff_script (struct change *script) 38 { 39 begin_output (); 40 41 next0 = next1 = - files[0].prefix_lines; 42 print_script (script, find_change, print_sdiff_hunk); 43 44 print_sdiff_common_lines (files[0].valid_lines, files[1].valid_lines); 45 } 46 47 /* Tab from column FROM to column TO, where FROM <= TO. Yield TO. */ 48 49 static size_t 50 tab_from_to (size_t from, size_t to) 51 { 52 FILE *out = outfile; 53 size_t tab; 54 size_t tab_size = tabsize; 55 56 if (!expand_tabs) 57 for (tab = from + tab_size - from % tab_size; tab <= to; tab += tab_size) 58 { 59 putc ('\t', out); 60 from = tab; 61 } 62 while (from++ < to) 63 putc (' ', out); 64 return to; 65 } 66 67 /* Print the text for half an sdiff line. This means truncate to 68 width observing tabs, and trim a trailing newline. Return the 69 last column written (not the number of chars). */ 70 71 static size_t 72 print_half_line (char const *const *line, size_t indent, size_t out_bound) 73 { 74 FILE *out = outfile; 75 register size_t in_position = 0; 76 register size_t out_position = 0; 77 register char const *text_pointer = line[0]; 78 register char const *text_limit = line[1]; 79 mbstate_t mbstate = { 0 }; 80 81 while (text_pointer < text_limit) 82 { 83 char const *tp0 = text_pointer; 84 register char c = *text_pointer++; 85 86 switch (c) 87 { 88 case '\t': 89 { 90 size_t spaces = tabsize - in_position % tabsize; 91 if (in_position == out_position) 92 { 93 size_t tabstop = out_position + spaces; 94 if (expand_tabs) 95 { 96 if (out_bound < tabstop) 97 tabstop = out_bound; 98 for (; out_position < tabstop; out_position++) 99 putc (' ', out); 100 } 101 else 102 if (tabstop < out_bound) 103 { 104 out_position = tabstop; 105 putc (c, out); 106 } 107 } 108 in_position += spaces; 109 } 110 break; 111 112 case '\r': 113 { 114 putc (c, out); 115 tab_from_to (0, indent); 116 in_position = out_position = 0; 117 } 118 break; 119 120 case '\b': 121 if (in_position != 0 && --in_position < out_bound) 122 { 123 if (out_position <= in_position) 124 /* Add spaces to make up for suppressed tab past out_bound. */ 125 for (; out_position < in_position; out_position++) 126 putc (' ', out); 127 else 128 { 129 out_position = in_position; 130 putc (c, out); 131 } 132 } 133 break; 134 135 default: 136 { 137 wchar_t wc; 138 size_t bytes = mbrtowc (&wc, tp0, text_limit - tp0, &mbstate); 139 140 if (0 < bytes && bytes < (size_t) -2) 141 { 142 int width = special_wcwidth (wc); 143 if (0 < width) 144 in_position += width; 145 if (in_position <= out_bound) 146 { 147 out_position = in_position; 148 fwrite (tp0, 1, bytes, stdout); 149 } 150 text_pointer = tp0 + bytes; 151 break; 152 } 153 } 154 /* Fall through. */ 155 case '\f': 156 case '\v': 157 if (in_position < out_bound) 158 putc (c, out); 159 break; 160 161 case ' ': case '!': case '"': case '#': case '%': 162 case '&': case '\'': case '(': case ')': case '*': 163 case '+': case ',': case '-': case '.': case '/': 164 case '0': case '1': case '2': case '3': case '4': 165 case '5': case '6': case '7': case '8': case '9': 166 case ':': case ';': case '<': case '=': case '>': 167 case '?': 168 case 'A': case 'B': case 'C': case 'D': case 'E': 169 case 'F': case 'G': case 'H': case 'I': case 'J': 170 case 'K': case 'L': case 'M': case 'N': case 'O': 171 case 'P': case 'Q': case 'R': case 'S': case 'T': 172 case 'U': case 'V': case 'W': case 'X': case 'Y': 173 case 'Z': 174 case '[': case '\\': case ']': case '^': case '_': 175 case 'a': case 'b': case 'c': case 'd': case 'e': 176 case 'f': case 'g': case 'h': case 'i': case 'j': 177 case 'k': case 'l': case 'm': case 'n': case 'o': 178 case 'p': case 'q': case 'r': case 's': case 't': 179 case 'u': case 'v': case 'w': case 'x': case 'y': 180 case 'z': case '{': case '|': case '}': case '~': 181 /* These characters are printable ASCII characters. */ 182 if (in_position++ < out_bound) 183 { 184 out_position = in_position; 185 putc (c, out); 186 } 187 break; 188 189 case '\n': 190 return out_position; 191 } 192 } 193 194 return out_position; 195 } 196 197 /* Print side by side lines with a separator in the middle. 198 0 parameters are taken to indicate white space text. 199 Blank lines that can easily be caught are reduced to a single newline. */ 200 201 static void 202 print_1sdiff_line (char const *const *left, char sep, 203 char const *const *right) 204 { 205 FILE *out = outfile; 206 size_t hw = sdiff_half_width; 207 size_t c2o = sdiff_column2_offset; 208 size_t col = 0; 209 bool put_newline = false; 210 211 if (left) 212 { 213 put_newline |= left[1][-1] == '\n'; 214 col = print_half_line (left, 0, hw); 215 } 216 217 if (sep != ' ') 218 { 219 col = tab_from_to (col, (hw + c2o - 1) / 2) + 1; 220 if (sep == '|' && put_newline != (right[1][-1] == '\n')) 221 sep = put_newline ? '/' : '\\'; 222 putc (sep, out); 223 } 224 225 if (right) 226 { 227 put_newline |= right[1][-1] == '\n'; 228 if (**right != '\n') 229 { 230 col = tab_from_to (col, c2o); 231 print_half_line (right, col, hw); 232 } 233 } 234 235 if (put_newline) 236 putc ('\n', out); 237 } 238 239 /* Print lines common to both files in side-by-side format. */ 240 static void 241 print_sdiff_common_lines (lin limit0, lin limit1) 242 { 243 lin i0 = next0, i1 = next1; 244 245 if (!suppress_common_lines && (i0 != limit0 || i1 != limit1)) 246 { 247 if (sdiff_merge_assist) 248 { 249 long int len0 = limit0 - i0; 250 long int len1 = limit1 - i1; 251 fprintf (outfile, "i%ld,%ld\n", len0, len1); 252 } 253 254 if (!left_column) 255 { 256 while (i0 != limit0 && i1 != limit1) 257 print_1sdiff_line (&files[0].linbuf[i0++], ' ', 258 &files[1].linbuf[i1++]); 259 while (i1 != limit1) 260 print_1sdiff_line (0, ')', &files[1].linbuf[i1++]); 261 } 262 while (i0 != limit0) 263 print_1sdiff_line (&files[0].linbuf[i0++], '(', 0); 264 } 265 266 next0 = limit0; 267 next1 = limit1; 268 } 269 270 /* Print a hunk of an sdiff diff. 271 This is a contiguous portion of a complete edit script, 272 describing changes in consecutive lines. */ 273 274 static void 275 print_sdiff_hunk (struct change *hunk) 276 { 277 lin first0, last0, first1, last1; 278 register lin i, j; 279 280 /* Determine range of line numbers involved in each file. */ 281 enum changes changes = 282 analyze_hunk (hunk, &first0, &last0, &first1, &last1); 283 if (!changes) 284 return; 285 286 /* Print out lines up to this change. */ 287 print_sdiff_common_lines (first0, first1); 288 289 if (sdiff_merge_assist) 290 { 291 long int len0 = last0 - first0 + 1; 292 long int len1 = last1 - first1 + 1; 293 fprintf (outfile, "c%ld,%ld\n", len0, len1); 294 } 295 296 /* Print "xxx | xxx " lines. */ 297 if (changes == CHANGED) 298 { 299 for (i = first0, j = first1; i <= last0 && j <= last1; i++, j++) 300 print_1sdiff_line (&files[0].linbuf[i], '|', &files[1].linbuf[j]); 301 changes = (i <= last0 ? OLD : 0) + (j <= last1 ? NEW : 0); 302 next0 = first0 = i; 303 next1 = first1 = j; 304 } 305 306 /* Print " > xxx " lines. */ 307 if (changes & NEW) 308 { 309 for (j = first1; j <= last1; ++j) 310 print_1sdiff_line (0, '>', &files[1].linbuf[j]); 311 next1 = j; 312 } 313 314 /* Print "xxx < " lines. */ 315 if (changes & OLD) 316 { 317 for (i = first0; i <= last0; ++i) 318 print_1sdiff_line (&files[0].linbuf[i], '<', 0); 319 next0 = i; 320 } 321 } 322