builtin/patch-id.c

   1 #include "cache.h"
   2 #include "builtin.h"
   3 #include "config.h"
   4 #include "diff.h"
   5 #include "parse-options.h"
   6
   7 static void flush_current_id(int patchlen, struct object_id *id, struct object_id *result)
   8 {
   9         if (patchlen)
  10                 printf("%s %s\n", oid_to_hex(result), oid_to_hex(id));
  11 }
  12
  13 static int remove_space(char *line)
  14 {
  15         char *src = line;
  16         char *dst = line;
  17         unsigned char c;
  18
  19         while ((c = *src++) != '\0') {
  20                 if (!isspace(c))
  21                         *dst++ = c;
  22         }
  23         return dst - line;
  24 }
  25
  26 static int scan_hunk_header(const char *p, int *p_before, int *p_after)
  27 {
  28         static const char digits[] = "0123456789";
  29         const char *q, *r;
  30         int n;
  31
  32         q = p + 4;
  33         n = strspn(q, digits);
  34         if (q[n] == ',') {
  35                 q += n + 1;
  36                 *p_before = atoi(q);
  37                 n = strspn(q, digits);
  38         } else {
  39                 *p_before = 1;
  40         }
  41
  42         if (n == 0 || q[n] != ' ' || q[n+1] != '+')
  43                 return 0;
  44
  45         r = q + n + 2;
  46         n = strspn(r, digits);
  47         if (r[n] == ',') {
  48                 r += n + 1;
  49                 *p_after = atoi(r);
  50                 n = strspn(r, digits);
  51         } else {
  52                 *p_after = 1;
  53         }
  54         if (n == 0)
  55                 return 0;
  56
  57         return 1;
  58 }
  59
  60 static int get_one_patchid(struct object_id *next_oid, struct object_id *result,
  61                            struct strbuf *line_buf, int stable, int verbatim)
  62 {
  63         int patchlen = 0, found_next = 0;
  64         int before = -1, after = -1;
  65         int diff_is_binary = 0;
  66         char pre_oid_str[GIT_MAX_HEXSZ + 1], post_oid_str[GIT_MAX_HEXSZ + 1];
  67         git_hash_ctx ctx;
  68
  69         the_hash_algo->init_fn(&ctx);
  70         oidclr(result);
  71
  72         while (strbuf_getwholeline(line_buf, stdin, '\n') != EOF) {
  73                 char *line = line_buf->buf;
  74                 const char *p = line;
  75                 int len;
  76
  77                 /* Possibly skip over the prefix added by "log" or "format-patch" */
  78                 if (!skip_prefix(line, "commit ", &p) &&
  79                     !skip_prefix(line, "From ", &p) &&
  80                     starts_with(line, "\\ ") && 12 < strlen(line)) {
  81                         if (verbatim)
  82                                 the_hash_algo->update_fn(&ctx, line, strlen(line));
  83                         continue;
  84                 }
  85
  86                 if (!get_oid_hex(p, next_oid)) {
  87                         found_next = 1;
  88                         break;
  89                 }
  90
  91                 /* Ignore commit comments */
  92                 if (!patchlen && !starts_with(line, "diff "))
  93                         continue;
  94
  95                 /* Parsing diff header?  */
  96                 if (before == -1) {
  97                         if (starts_with(line, "GIT binary patch") ||
  98                             starts_with(line, "Binary files")) {
  99                                 diff_is_binary = 1;
 100                                 before = 0;
 101                                 the_hash_algo->update_fn(&ctx, pre_oid_str,
 102                                                          strlen(pre_oid_str));
 103                                 the_hash_algo->update_fn(&ctx, post_oid_str,
 104                                                          strlen(post_oid_str));
 105                                 if (stable)
 106                                         flush_one_hunk(result, &ctx);
 107                                 continue;
 108                         } else if (skip_prefix(line, "index ", &p)) {
 109                                 char *oid1_end = strstr(line, "..");
 110                                 char *oid2_end = NULL;
 111                                 if (oid1_end)
 112                                         oid2_end = strstr(oid1_end, " ");
 113                                 if (!oid2_end)
 114                                         oid2_end = line + strlen(line) - 1;
 115                                 if (oid1_end != NULL && oid2_end != NULL) {
 116                                         *oid1_end = *oid2_end = '\0';
 117                                         strlcpy(pre_oid_str, p, GIT_MAX_HEXSZ + 1);
 118                                         strlcpy(post_oid_str, oid1_end + 2, GIT_MAX_HEXSZ + 1);
 119                                 }
 120                                 continue;
 121                         } else if (starts_with(line, "--- "))
 122                                 before = after = 1;
 123                         else if (!isalpha(line[0]))
 124                                 break;
 125                 }
 126
 127                 if (diff_is_binary) {
 128                         if (starts_with(line, "diff ")) {
 129                                 diff_is_binary = 0;
 130                                 before = -1;
 131                         }
 132                         continue;
 133                 }
 134
 135                 /* Looking for a valid hunk header?  */
 136                 if (before == 0 && after == 0) {
 137                         if (starts_with(line, "@@ -")) {
 138                                 /* Parse next hunk, but ignore line numbers.  */
 139                                 scan_hunk_header(line, &before, &after);
 140                                 continue;
 141                         }
 142
 143                         /* Split at the end of the patch.  */
 144                         if (!starts_with(line, "diff "))
 145                                 break;
 146
 147                         /* Else we're parsing another header.  */
 148                         if (stable)
 149                                 flush_one_hunk(result, &ctx);
 150                         before = after = -1;
 151                 }
 152
 153                 /* If we get here, we're inside a hunk.  */
 154                 if (line[0] == '-' || line[0] == ' ')
 155                         before--;
 156                 if (line[0] == '+' || line[0] == ' ')
 157                         after--;
 158
 159                 /* Add line to hash algo (possibly removing whitespace) */
 160                 len = verbatim ? strlen(line) : remove_space(line);
 161                 patchlen += len;
 162                 the_hash_algo->update_fn(&ctx, line, len);
 163         }
 164
 165         if (!found_next)
 166                 oidclr(next_oid);
 167
 168         flush_one_hunk(result, &ctx);
 169
 170         return patchlen;
 171 }
 172
 173 static void generate_id_list(int stable, int verbatim)
 174 {
 175         struct object_id oid, n, result;
 176         int patchlen;
 177         struct strbuf line_buf = STRBUF_INIT;
 178
 179         oidclr(&oid);
 180         while (!feof(stdin)) {
 181                 patchlen = get_one_patchid(&n, &result, &line_buf, stable, verbatim);
 182                 flush_current_id(patchlen, &oid, &result);
 183                 oidcpy(&oid, &n);
 184         }
 185         strbuf_release(&line_buf);
 186 }
 187
 188 static const char *const patch_id_usage[] = {
 189         N_("git patch-id [--stable | --unstable | --verbatim]"), NULL
 190 };
 191
 192 struct patch_id_opts {
 193         int stable;
 194         int verbatim;
 195 };
 196
 197 static int git_patch_id_config(const char *var, const char *value, void *cb)
 198 {
 199         struct patch_id_opts *opts = cb;
 200
 201         if (!strcmp(var, "patchid.stable")) {
 202                 opts->stable = git_config_bool(var, value);
 203                 return 0;
 204         }
 205         if (!strcmp(var, "patchid.verbatim")) {
 206                 opts->verbatim = git_config_bool(var, value);
 207                 return 0;
 208         }
 209
 210         return git_default_config(var, value, cb);
 211 }
 212
 213 int cmd_patch_id(int argc, const char **argv, const char *prefix)
 214 {
 215         /* if nothing is set, default to unstable */
 216         struct patch_id_opts config = {0, 0};
 217         int opts = 0;
 218         struct option builtin_patch_id_options[] = {
 219                 OPT_CMDMODE(0, "unstable", &opts,
 220                     N_("use the unstable patch-id algorithm"), 1),
 221                 OPT_CMDMODE(0, "stable", &opts,
 222                     N_("use the stable patch-id algorithm"), 2),
 223                 OPT_CMDMODE(0, "verbatim", &opts,
 224                         N_("don't strip whitespace from the patch"), 3),
 225                 OPT_END()
 226         };
 227
 228         git_config(git_patch_id_config, &config);
 229
 230         /* verbatim implies stable */
 231         if (config.verbatim)
 232                 config.stable = 1;
 233
 234         argc = parse_options(argc, argv, prefix, builtin_patch_id_options,
 235                              patch_id_usage, 0);
 236
 237         generate_id_list(opts ? opts > 1 : config.stable,
 238                          opts ? opts == 3 : config.verbatim);
 239         return 0;
 240 }