wiggle.h

   1 /*
   2  * wiggle - apply rejected patches
   3  *
   4  * Copyright (C) 2003-2013 Neil Brown <neilb@suse.de>
   5  *
   6  *
   7  *    This program is free software; you can redistribute it and/or modify
   8  *    it under the terms of the GNU General Public License as published by
   9  *    the Free Software Foundation; either version 2 of the License, or
  10  *    (at your option) any later version.
  11  *
  12  *    This program is distributed in the hope that it will be useful,
  13  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *    GNU General Public License for more details.
  16  *
  17  *    You should have received a copy of the GNU General Public License
  18  *    along with this program.
  19  *
  20  *    Author: Neil Brown
  21  *    Email: <neilb@suse.de>
  22  */
  23
  24 #define _GNU_SOURCE /* for asprintf */
  25 #include        <stdio.h>
  26 #include        <string.h>
  27 #include        <memory.h>
  28 #include        <getopt.h>
  29 #include        <stdlib.h>
  30
  31 static inline void assert(int a)
  32 {
  33         if (!a)
  34                 abort();
  35 }
  36
  37 struct stream {
  38         char *body;
  39         int len;
  40 };
  41
  42 /* an 'elmnt' is a word or a line from the file.
  43  * 'start' points into a 'body' in a stream.
  44  * When a stream is made of 'diff' hunks, there is a special
  45  * elmnt at the start of each hunk which starts with '\0' and
  46  * records the line offsets of the hunk.  These are 20+ bytes long.
  47  * "\0\d{5} \d{5} \d{5}{SP funcname}?\n\0"
  48  * The 3 numbers are: chunk number, starting line, number of lines.
  49  * An element with len==0 marks EOF.
  50  */
  51 struct elmnt {
  52         char *start;
  53         int hash;
  54         short len, plen, prefix;
  55 };
  56
  57 static inline int match(struct elmnt *a, struct elmnt *b)
  58 {
  59         return
  60                 a->hash == b->hash &&
  61                 ((a->start[0] == 0 && b->start[0] == 0)
  62                  ||
  63                  (a->len == b->len &&
  64                   strncmp(a->start, b->start, a->len) == 0));
  65 }
  66
  67 /* end-of-line is important for narrowing conflicts.
  68  * In line mode, every element is a line and 'ends a line'
  69  * In word mode, the newline element and the diff-hunk element
  70  * end a line.
  71  */
  72 static inline int ends_line(struct elmnt e)
  73 {
  74         if (e.len >= 20 && e.start[0] == 0)
  75                 return 1;
  76         return e.len &&  e.start[e.plen-1] == '\n';
  77 }
  78
  79 struct csl {
  80         int a, b;
  81         int len;
  82 };
  83
  84 struct file {
  85         struct elmnt *list;
  86         int elcnt;
  87 };
  88
  89 /* The result of a merger is a series of text sections.
  90  * Each section may occur in one or more of the three stream,
  91  * and may be different in different stream (e.g. for changed text)
  92  * or the same.
  93  * When a conflict occurs we need to treat some surrounding
  94  * sections as being involved in that conflict.  For
  95  * line-based merging, all surrounding sections until an Unchanged
  96  * section are part of the conflict - the Unchanged isn't.
  97  * For word-based merging, we need to find Unchanged sections
  98  * that include a newline.  Further, text within the unchanged
  99  * section upto the newline (in whichever direction) is treated
 100  * as part of the whole conflict.
 101  * Actually... it is possibly for a 'Changed' section to bound
 102  * a conflict as it indicates a successful match of A and B.
 103  * For line-wise merges, any Changed or Unchanged section bounds a conflict
 104  * For word-wise merges, any Changed or Unchanged section that matches
 105  * a newline, or immediately follows a newline (in all files) can bound
 106  * a conflict.
 107  */
 108 struct merge {
 109         enum mergetype {
 110                 End, Unmatched, Unchanged, Extraneous,
 111                 Changed, Conflict, AlreadyApplied,
 112         } type, oldtype;
 113         int a, b, c; /* start of ranges */
 114         int al, bl, cl; /* length of ranges */
 115         int c1, c2; /* this or next common-sequence */
 116         int in_conflict;
 117         int lo, hi; /* region of a Changed or Unchanged that is not involved
 118                     * in a conflict.
 119                     * These are distances from start of the "before" section,
 120                     * not indexes into any file.
 121                     */
 122
 123 };
 124
 125 /* plist stores a list of patched files in an array
 126  * Each entry identifies a file, the range of the
 127  * original patch which applies to this file, some
 128  * statistics concerning how many conflicts etc, and
 129  * some linkage information so the list can be viewed
 130  * as a directory-tree.
 131  */
 132 struct plist {
 133         char *file, *outfile;
 134         unsigned int start, end;
 135         int parent;
 136         int next, prev, last;
 137         int open;
 138         int chunks, wiggles, conflicts;
 139         int calced;
 140         int is_merge;
 141         char *before, *after;
 142 };
 143
 144 extern struct plist *sort_patches(struct plist *pl, int *np);
 145 extern void plist_free(struct plist *pl, int num);
 146 extern struct plist *parse_patch(FILE *f, FILE *of, int *np);
 147 extern struct stream load_segment(FILE *f, unsigned int start,
 148                                   unsigned int end);
 149 extern int set_prefix(struct plist *pl, int n, int strip);
 150 extern struct stream load_file(char *name);
 151 extern int split_patch(struct stream, struct stream*, struct stream*);
 152 extern int split_merge(struct stream, struct stream*, struct stream*,
 153                        struct stream*);
 154 extern struct file split_stream(struct stream s, int type);
 155 extern struct csl *pdiff(struct file a, struct file b, int chunks);
 156 extern struct csl *diff(struct file a, struct file b, int shortest);
 157 extern struct csl *diff_patch(struct file a, struct file b, int shortest);
 158 extern struct csl *diff_partial(struct file a, struct file b,
 159                                 int alo, int ahi, int blo, int bhi);
 160 extern struct csl *worddiff(struct stream f1, struct stream f2,
 161                             struct file *fl1p, struct file *fl2p);
 162 extern struct csl *csl_join(struct csl *c1, struct csl *c2);
 163
 164 struct ci {
 165         int conflicts, wiggles, ignored;
 166         struct merge *merger;
 167 };
 168 extern int print_merge(FILE *out,
 169                        struct file *a, struct file *b, struct file *c,
 170                        int words, struct merge *merger,
 171                        struct merge *mpos, int streampos, int offsetpos);
 172 extern void printword(FILE *f, struct elmnt e);
 173 extern int save_merge(struct file a, struct file b, struct file c,
 174                       struct merge *merger, char *file, int backup);
 175 extern int save_tmp_merge(struct file a, struct file b, struct file c,
 176                           struct merge *merger, char **filep,
 177                           struct merge *mpos, int streampos, int offsetpos);
 178
 179 extern int isolate_conflicts(struct file af, struct file bf, struct file cf,
 180                              struct csl *csl1, struct csl *csl2, int words,
 181                              struct merge *m, int show_wiggles, int *wigglesp);
 182 extern struct ci make_merger(struct file a, struct file b, struct file c,
 183                              struct csl *c1, struct csl *c2, int words,
 184                              int ignore_already, int show_wiggles);
 185
 186 extern void die(char *reason);
 187 extern void check_dir(char *name, int fd);
 188 extern void *xmalloc(int len);
 189 extern int do_trace;
 190
 191 extern int vpatch(int argc, char *argv[], int patch, int strip,
 192                   int reverse, int replace, char *outfile,
 193                   int selftest,
 194                   int ignore_blanks, int backup);
 195
 196 extern char *Cmd;
 197 extern char Version[];
 198 extern char short_options[];
 199 extern struct option long_options[];
 200 enum other_options {
 201         SELF_TEST = 300,
 202         REPORT_WIGGLES,
 203         NO_BACKUP,
 204         NON_SPACE,
 205         SHORTEST,
 206 };
 207 extern char Usage[];
 208 extern char Help[];
 209 extern char HelpExtract[];
 210 extern char HelpDiff[];
 211 extern char HelpMerge[];
 212 extern char HelpBrowse[];
 213
 214 extern void cleanlist(struct file a, struct file b, struct csl *list);
 215
 216 enum {
 217         ByLine = 0,
 218         ByWord = 1,
 219         ByMask = 3,
 220         IgnoreBlanks = 8, /* 'or'ed in */
 221         WholeWord = 16,
 222 };