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vtools_genesis          1 
vtools_genesis          2 #include <stdlib.h>
vtools_genesis          3 #include "diff.h"
vtools_genesis          4 
vtools_genesis          5 /* Print a label for a context diff, with a file name and date or a
vtools_genesis          6    label.  */
vtools_genesis          7 
vtools_genesis          8 static void
vtools_genesis          9 print_context_label(char const *mark,
vtools_genesis         10                     struct file_data *inf,
vtools_genesis         11                     char const *name,
vtools_genesis         12                     char const *label) {
vtools_genesis         13     if (label)
vtools_genesis         14         fprintf(outfile, "%s %s\n", mark, label);
vtools_genesis         15     else {
vtools_genesis         16         fprintf(outfile, "%s %s false\n", mark, name);
vtools_genesis         17     }
vtools_genesis         18 }
vtools_genesis         19 
vtools_genesis         20 /* Print a header for a context diff, with the file names and dates.  */
vtools_genesis         21 
vtools_genesis         22 void
vtools_genesis         23 print_context_header(struct file_data inf[], char const *const *names) {
vtools_genesis         24     print_context_label("---", &inf[0], names[0], file_label[0]);
vtools_genesis         25     print_context_label("+++", &inf[1], names[1], file_label[1]);
vtools_genesis         26 }
vtools_genesis         27 
vtools_genesis         28 /* Print an edit script in context format.  */
vtools_genesis         29 
vtools_genesis         30 void
vtools_genesis         31 print_context_script(struct change *script) {
vtools_genesis         32     struct change *e;
vtools_genesis         33     for (e = script; e; e = e->link)
vtools_genesis         34         e->ignore = false;
vtools_genesis         35 
vtools_genesis         36     print_script(script);
vtools_genesis         37 }
vtools_genesis         38 
vtools_genesis         39 /* Print a pair of line numbers with a comma, translated for file
vtools_genesis         40    |file|.  If the second number is smaller, use the first in place of
vtools_genesis         41    it.  If the numbers are equal, print just one number.
vtools_genesis         42 
vtools_genesis         43    Args |a| and |b| are internal line numbers.  We print the
vtools_genesis         44    translated (real) line numbers.  */
vtools_genesis         45 
vtools_genesis         46 static void
vtools_genesis         47 print_unidiff_number_range(struct file_data const *file, lin a, lin b) {
vtools_genesis         48     printint trans_a, trans_b;
vtools_genesis         49     translate_range(file, a, b, &trans_a, &trans_b);
vtools_genesis         50 
vtools_genesis         51     /* We can have |b < a| in the case of a range of no lines.  In
vtools_genesis         52        this case, we print the line number before the range, which is
vtools_genesis         53        |b|.  It would be more logical to print |a|, but `patch'
vtools_genesis         54        expects |b| in order to detect diffs against empty files.  */
vtools_genesis         55     if (trans_b <= trans_a)
vtools_genesis         56         fprintf(outfile, trans_b < trans_a ? "%"pI"d,0" : "%"pI"d", trans_b);
vtools_genesis         57     else
vtools_genesis         58         fprintf(outfile, "%"pI"d,%"pI"d", trans_a, trans_b - trans_a + 1);
vtools_genesis         59 }
vtools_genesis         60 
vtools_genesis         61 /* Print a portion of an edit script in unidiff format.  |hunk| is the
vtools_genesis         62    beginning of the portion to be printed.  The end is marked by a
vtools_genesis         63    |link| that has been nulled out.
vtools_genesis         64 
vtools_genesis         65    Prints out lines from both files, and precedes each line with the
vtools_genesis         66    appropriate flag-character.  */
vtools_genesis         67 
vtools_genesis         68 void
vtools_genesis         69 pr_unidiff_hunk(struct change *hunk) {
vtools_genesis         70     lin first0, last0, first1, last1;
vtools_genesis         71     lin i, j, k;
vtools_genesis         72     struct change *next;
vtools_genesis         73     FILE *out;
vtools_genesis         74 
vtools_genesis         75     /* Determine range of line numbers involved in each file.  */
vtools_genesis         76 
vtools_genesis         77     if (!analyze_hunk(hunk, &first0, &last0, &first1, &last1))
vtools_genesis         78         return;
vtools_genesis         79 
vtools_genesis         80     /* Include a context's width before and after.  */
vtools_genesis         81 
vtools_genesis         82     i = -files[0].prefix_lines;
vtools_genesis         83     first0 = MAX (first0 - context, i);
vtools_genesis         84     first1 = MAX (first1 - context, i);
vtools_genesis         85     if (last0 < files[0].valid_lines - context)
vtools_genesis         86         last0 += context;
vtools_genesis         87     else
vtools_genesis         88         last0 = files[0].valid_lines - 1;
vtools_genesis         89     if (last1 < files[1].valid_lines - context)
vtools_genesis         90         last1 += context;
vtools_genesis         91     else
vtools_genesis         92         last1 = files[1].valid_lines - 1;
vtools_genesis         93 
vtools_genesis         94     begin_output();
vtools_genesis         95     out = outfile;
vtools_genesis         96 
vtools_genesis         97     fputs("@@ -", out);
vtools_genesis         98     print_unidiff_number_range(&files[0], first0, last0);
vtools_genesis         99     fputs(" +", out);
vtools_genesis        100     print_unidiff_number_range(&files[1], first1, last1);
vtools_genesis        101     fputs(" @@", out);
vtools_genesis        102 
vtools_genesis        103     putc('\n', out);
vtools_genesis        104 
vtools_genesis        105     next = hunk;
vtools_genesis        106     i = first0;
vtools_genesis        107     j = first1;
vtools_genesis        108 
vtools_genesis        109     while (i <= last0 || j <= last1) {
vtools_genesis        110 
vtools_genesis        111         /* If the line isn't a difference, output the context from
vtools_genesis        112            file 0. */
vtools_genesis        113 
vtools_genesis        114         if (!next || i < next->line0) {
vtools_genesis        115             char const *const *line = &files[0].linbuf[i++];
vtools_genesis        116             if (!(suppress_blank_empty && **line == '\n'))
vtools_genesis        117                 putc(' ', out);
vtools_genesis        118             print_1_line(NULL, line);
vtools_genesis        119             j++;
vtools_genesis        120         } else {
vtools_genesis        121             /* For each difference, first output the deleted part. */
vtools_genesis        122 
vtools_genesis        123             k = next->deleted;
vtools_genesis        124             while (k--) {
vtools_genesis        125                 char const *const *line = &files[0].linbuf[i++];
vtools_genesis        126                 putc('-', out);
vtools_genesis        127                 print_1_line_nl(NULL, line, true);
vtools_genesis        128                 if (line[1][-1] == '\n')
vtools_genesis        129                     putc('\n', out);
vtools_genesis        130             }
vtools_genesis        131 
vtools_genesis        132             /* Then output the inserted part. */
vtools_genesis        133 
vtools_genesis        134             k = next->inserted;
vtools_genesis        135             while (k--) {
vtools_genesis        136                 char const *const *line = &files[1].linbuf[j++];
vtools_genesis        137                 putc('+', out);
vtools_genesis        138                 print_1_line_nl(NULL, line, true);
vtools_genesis        139                 if (line[1][-1] == '\n')
vtools_genesis        140                     putc('\n', out);
vtools_genesis        141             }
vtools_genesis        142 
vtools_genesis        143             /* We're done with this hunk, so on to the next! */
vtools_genesis        144 
vtools_genesis        145             next = next->link;
vtools_genesis        146         }
vtools_genesis        147     }
vtools_genesis        148 }
vtools_genesis        149 
vtools_genesis        150 /* Scan a (forward-ordered) edit script for the first place that more
vtools_genesis        151    than |2*context| unchanged lines appear, and return a pointer to
vtools_genesis        152    the |struct change| for the last change before those lines.  */
vtools_genesis        153 
vtools_genesis        154 struct change *
vtools_genesis        155 find_hunk(struct change *start) {
vtools_genesis        156     struct change *prev;
vtools_genesis        157     lin top0, top1;
vtools_genesis        158     lin thresh;
vtools_genesis        159 
vtools_genesis        160     /* Threshold distance is |context| if the second change is
vtools_genesis        161        ignorable, |2 * context + 1| otherwise.  Integer overflow can't
vtools_genesis        162        happen, due to |CONTEXT_LIM|.  */
vtools_genesis        163     lin ignorable_threshold = context;
vtools_genesis        164     lin non_ignorable_threshold = 2 * context + 1;
vtools_genesis        165 
vtools_genesis        166     do {
vtools_genesis        167         /* Compute number of first line in each file beyond this changed.  */
vtools_genesis        168         top0 = start->line0 + start->deleted;
vtools_genesis        169         top1 = start->line1 + start->inserted;
vtools_genesis        170         prev = start;
vtools_genesis        171         start = start->link;
vtools_genesis        172         thresh = (start && start->ignore
vtools_genesis        173                   ? ignorable_threshold
vtools_genesis        174                   : non_ignorable_threshold);
vtools_genesis        175         /* It is not supposed to matter which file we check in the
vtools_genesis        176        end-test.  If it would matter, crash.  */
vtools_genesis        177         if (start && start->line0 - top0 != start->line1 - top1)
vtools_genesis        178             abort();
vtools_genesis        179     } while (start
vtools_genesis        180              /* Keep going if less than |thresh| lines elapse before
vtools_genesis        181             the affected line.  */
vtools_genesis        182              && start->line0 - top0 < thresh);
vtools_genesis        183 
vtools_genesis        184     return prev;
vtools_genesis        185 }
vtools_genesis        186 
vtools_genesis        187 /* Set the |ignore| flag properly in each change in script.  It should
vtools_genesis        188    be 1 if all the lines inserted or deleted in that change are
vtools_genesis        189    ignorable lines.  */
vtools_genesis        190 
vtools_genesis        191 static void
vtools_genesis        192 mark_ignorable(struct change *script) {
vtools_genesis        193     while (script) {
vtools_genesis        194         struct change *next = script->link;
vtools_genesis        195         lin first0, last0, first1, last1;
vtools_genesis        196 
vtools_genesis        197         /* Turn this change into a hunk: detach it from the others.  */
vtools_genesis        198         script->link = NULL;
vtools_genesis        199 
vtools_genesis        200         /* Determine whether this change is ignorable.  */
vtools_genesis        201         script->ignore = !analyze_hunk(script,
vtools_genesis        202                                        &first0, &last0, &first1, &last1);
vtools_genesis        203 
vtools_genesis        204         /* Reconnect the chain as before.  */
vtools_genesis        205         script->link = next;
vtools_genesis        206 
vtools_genesis        207         /* Advance to the following change.  */
vtools_genesis        208         script = next;
vtools_genesis        209     }
vtools_genesis        210 }
vtools_genesis        211