builtin/patch-id.c

   1 #include "cache.h"
   2 #include "builtin.h"
   3 #include "config.h"
   4 #include "diff.h"
   5
   6 static void flush_current_id(int patchlen, struct object_id *id, struct object_id *result)
   7 {
   8         if (patchlen)
   9                 printf("%s %s\n", oid_to_hex(result), oid_to_hex(id));
  10 }
  11
  12 static int remove_space(char *line)
  13 {
  14         char *src = line;
  15         char *dst = line;
  16         unsigned char c;
  17
  18         while ((c = *src++) != '\0') {
  19                 if (!isspace(c))
  20                         *dst++ = c;
  21         }
  22         return dst - line;
  23 }
  24
  25 static int scan_hunk_header(const char *p, int *p_before, int *p_after)
  26 {
  27         static const char digits[] = "0123456789";
  28         const char *q, *r;
  29         int n;
  30
  31         q = p + 4;
  32         n = strspn(q, digits);
  33         if (q[n] == ',') {
  34                 q += n + 1;
  35                 *p_before = atoi(q);
  36                 n = strspn(q, digits);
  37         } else {
  38                 *p_before = 1;
  39         }
  40
  41         if (n == 0 || q[n] != ' ' || q[n+1] != '+')
  42                 return 0;
  43
  44         r = q + n + 2;
  45         n = strspn(r, digits);
  46         if (r[n] == ',') {
  47                 r += n + 1;
  48                 *p_after = atoi(r);
  49                 n = strspn(r, digits);
  50         } else {
  51                 *p_after = 1;
  52         }
  53         if (n == 0)
  54                 return 0;
  55
  56         return 1;
  57 }
  58
  59 static int get_one_patchid(struct object_id *next_oid, struct object_id *result,
  60                            struct strbuf *line_buf, int stable)
  61 {
  62         int patchlen = 0, found_next = 0;
  63         int before = -1, after = -1;
  64         git_hash_ctx ctx;
  65
  66         the_hash_algo->init_fn(&ctx);
  67         oidclr(result);
  68
  69         while (strbuf_getwholeline(line_buf, stdin, '\n') != EOF) {
  70                 char *line = line_buf->buf;
  71                 const char *p = line;
  72                 int len;
  73
  74                 if (!skip_prefix(line, "diff-tree ", &p) &&
  75                     !skip_prefix(line, "commit ", &p) &&
  76                     !skip_prefix(line, "From ", &p) &&
  77                     starts_with(line, "\\ ") && 12 < strlen(line))
  78                         continue;
  79
  80                 if (!get_oid_hex(p, next_oid)) {
  81                         found_next = 1;
  82                         break;
  83                 }
  84
  85                 /* Ignore commit comments */
  86                 if (!patchlen && !starts_with(line, "diff "))
  87                         continue;
  88
  89                 /* Parsing diff header?  */
  90                 if (before == -1) {
  91                         if (starts_with(line, "index "))
  92                                 continue;
  93                         else if (starts_with(line, "--- "))
  94                                 before = after = 1;
  95                         else if (!isalpha(line[0]))
  96                                 break;
  97                 }
  98
  99                 /* Looking for a valid hunk header?  */
 100                 if (before == 0 && after == 0) {
 101                         if (starts_with(line, "@@ -")) {
 102                                 /* Parse next hunk, but ignore line numbers.  */
 103                                 scan_hunk_header(line, &before, &after);
 104                                 continue;
 105                         }
 106
 107                         /* Split at the end of the patch.  */
 108                         if (!starts_with(line, "diff "))
 109                                 break;
 110
 111                         /* Else we're parsing another header.  */
 112                         if (stable)
 113                                 flush_one_hunk(result, &ctx);
 114                         before = after = -1;
 115                 }
 116
 117                 /* If we get here, we're inside a hunk.  */
 118                 if (line[0] == '-' || line[0] == ' ')
 119                         before--;
 120                 if (line[0] == '+' || line[0] == ' ')
 121                         after--;
 122
 123                 /* Compute the sha without whitespace */
 124                 len = remove_space(line);
 125                 patchlen += len;
 126                 the_hash_algo->update_fn(&ctx, line, len);
 127         }
 128
 129         if (!found_next)
 130                 oidclr(next_oid);
 131
 132         flush_one_hunk(result, &ctx);
 133
 134         return patchlen;
 135 }
 136
 137 static void generate_id_list(int stable)
 138 {
 139         struct object_id oid, n, result;
 140         int patchlen;
 141         struct strbuf line_buf = STRBUF_INIT;
 142
 143         oidclr(&oid);
 144         while (!feof(stdin)) {
 145                 patchlen = get_one_patchid(&n, &result, &line_buf, stable);
 146                 flush_current_id(patchlen, &oid, &result);
 147                 oidcpy(&oid, &n);
 148         }
 149         strbuf_release(&line_buf);
 150 }
 151
 152 static const char patch_id_usage[] = "git patch-id [--stable | --unstable]";
 153
 154 static int git_patch_id_config(const char *var, const char *value, void *cb)
 155 {
 156         int *stable = cb;
 157
 158         if (!strcmp(var, "patchid.stable")) {
 159                 *stable = git_config_bool(var, value);
 160                 return 0;
 161         }
 162
 163         return git_default_config(var, value, cb);
 164 }
 165
 166 int cmd_patch_id(int argc, const char **argv, const char *prefix)
 167 {
 168         int stable = -1;
 169
 170         git_config(git_patch_id_config, &stable);
 171
 172         /* If nothing is set, default to unstable. */
 173         if (stable < 0)
 174                 stable = 0;
 175
 176         if (argc == 2 && !strcmp(argv[1], "--stable"))
 177                 stable = 1;
 178         else if (argc == 2 && !strcmp(argv[1], "--unstable"))
 179                 stable = 0;
 180         else if (argc != 1)
 181                 usage(patch_id_usage);
 182
 183         generate_id_list(stable);
 184         return 0;
 185 }