builtin/patch-id.c

   1 #include "builtin.h"
   2 #include "config.h"
   3 #include "diff.h"
   4 #include "gettext.h"
   5 #include "hash.h"
   6 #include "hex.h"
   7 #include "parse-options.h"
   8
   9 static void flush_current_id(int patchlen, struct object_id *id, struct object_id *result)
  10 {
  11         if (patchlen)
  12                 printf("%s %s\n", oid_to_hex(result), oid_to_hex(id));
  13 }
  14
  15 static int remove_space(char *line)
  16 {
  17         char *src = line;
  18         char *dst = line;
  19         unsigned char c;
  20
  21         while ((c = *src++) != '\0') {
  22                 if (!isspace(c))
  23                         *dst++ = c;
  24         }
  25         return dst - line;
  26 }
  27
  28 static int scan_hunk_header(const char *p, int *p_before, int *p_after)
  29 {
  30         static const char digits[] = "0123456789";
  31         const char *q, *r;
  32         int n;
  33
  34         q = p + 4;
  35         n = strspn(q, digits);
  36         if (q[n] == ',') {
  37                 q += n + 1;
  38                 *p_before = atoi(q);
  39                 n = strspn(q, digits);
  40         } else {
  41                 *p_before = 1;
  42         }
  43
  44         if (n == 0 || q[n] != ' ' || q[n+1] != '+')
  45                 return 0;
  46
  47         r = q + n + 2;
  48         n = strspn(r, digits);
  49         if (r[n] == ',') {
  50                 r += n + 1;
  51                 *p_after = atoi(r);
  52                 n = strspn(r, digits);
  53         } else {
  54                 *p_after = 1;
  55         }
  56         if (n == 0)
  57                 return 0;
  58
  59         return 1;
  60 }
  61
  62 static int get_one_patchid(struct object_id *next_oid, struct object_id *result,
  63                            struct strbuf *line_buf, int stable, int verbatim)
  64 {
  65         int patchlen = 0, found_next = 0;
  66         int before = -1, after = -1;
  67         int diff_is_binary = 0;
  68         char pre_oid_str[GIT_MAX_HEXSZ + 1], post_oid_str[GIT_MAX_HEXSZ + 1];
  69         git_hash_ctx ctx;
  70
  71         the_hash_algo->init_fn(&ctx);
  72         oidclr(result);
  73
  74         while (strbuf_getwholeline(line_buf, stdin, '\n') != EOF) {
  75                 char *line = line_buf->buf;
  76                 const char *p = line;
  77                 int len;
  78
  79                 /* Possibly skip over the prefix added by "log" or "format-patch" */
  80                 if (!skip_prefix(line, "commit ", &p) &&
  81                     !skip_prefix(line, "From ", &p) &&
  82                     starts_with(line, "\\ ") && 12 < strlen(line)) {
  83                         if (verbatim)
  84                                 the_hash_algo->update_fn(&ctx, line, strlen(line));
  85                         continue;
  86                 }
  87
  88                 if (!get_oid_hex(p, next_oid)) {
  89                         found_next = 1;
  90                         break;
  91                 }
  92
  93                 /* Ignore commit comments */
  94                 if (!patchlen && !starts_with(line, "diff "))
  95                         continue;
  96
  97                 /* Parsing diff header?  */
  98                 if (before == -1) {
  99                         if (starts_with(line, "GIT binary patch") ||
 100                             starts_with(line, "Binary files")) {
 101                                 diff_is_binary = 1;
 102                                 before = 0;
 103                                 the_hash_algo->update_fn(&ctx, pre_oid_str,
 104                                                          strlen(pre_oid_str));
 105                                 the_hash_algo->update_fn(&ctx, post_oid_str,
 106                                                          strlen(post_oid_str));
 107                                 if (stable)
 108                                         flush_one_hunk(result, &ctx);
 109                                 continue;
 110                         } else if (skip_prefix(line, "index ", &p)) {
 111                                 char *oid1_end = strstr(line, "..");
 112                                 char *oid2_end = NULL;
 113                                 if (oid1_end)
 114                                         oid2_end = strstr(oid1_end, " ");
 115                                 if (!oid2_end)
 116                                         oid2_end = line + strlen(line) - 1;
 117                                 if (oid1_end != NULL && oid2_end != NULL) {
 118                                         *oid1_end = *oid2_end = '\0';
 119                                         strlcpy(pre_oid_str, p, GIT_MAX_HEXSZ + 1);
 120                                         strlcpy(post_oid_str, oid1_end + 2, GIT_MAX_HEXSZ + 1);
 121                                 }
 122                                 continue;
 123                         } else if (starts_with(line, "--- "))
 124                                 before = after = 1;
 125                         else if (!isalpha(line[0]))
 126                                 break;
 127                 }
 128
 129                 if (diff_is_binary) {
 130                         if (starts_with(line, "diff ")) {
 131                                 diff_is_binary = 0;
 132                                 before = -1;
 133                         }
 134                         continue;
 135                 }
 136
 137                 /* Looking for a valid hunk header?  */
 138                 if (before == 0 && after == 0) {
 139                         if (starts_with(line, "@@ -")) {
 140                                 /* Parse next hunk, but ignore line numbers.  */
 141                                 scan_hunk_header(line, &before, &after);
 142                                 continue;
 143                         }
 144
 145                         /* Split at the end of the patch.  */
 146                         if (!starts_with(line, "diff "))
 147                                 break;
 148
 149                         /* Else we're parsing another header.  */
 150                         if (stable)
 151                                 flush_one_hunk(result, &ctx);
 152                         before = after = -1;
 153                 }
 154
 155                 /* If we get here, we're inside a hunk.  */
 156                 if (line[0] == '-' || line[0] == ' ')
 157                         before--;
 158                 if (line[0] == '+' || line[0] == ' ')
 159                         after--;
 160
 161                 /* Add line to hash algo (possibly removing whitespace) */
 162                 len = verbatim ? strlen(line) : remove_space(line);
 163                 patchlen += len;
 164                 the_hash_algo->update_fn(&ctx, line, len);
 165         }
 166
 167         if (!found_next)
 168                 oidclr(next_oid);
 169
 170         flush_one_hunk(result, &ctx);
 171
 172         return patchlen;
 173 }
 174
 175 static void generate_id_list(int stable, int verbatim)
 176 {
 177         struct object_id oid, n, result;
 178         int patchlen;
 179         struct strbuf line_buf = STRBUF_INIT;
 180
 181         oidclr(&oid);
 182         while (!feof(stdin)) {
 183                 patchlen = get_one_patchid(&n, &result, &line_buf, stable, verbatim);
 184                 flush_current_id(patchlen, &oid, &result);
 185                 oidcpy(&oid, &n);
 186         }
 187         strbuf_release(&line_buf);
 188 }
 189
 190 static const char *const patch_id_usage[] = {
 191         N_("git patch-id [--stable | --unstable | --verbatim]"), NULL
 192 };
 193
 194 struct patch_id_opts {
 195         int stable;
 196         int verbatim;
 197 };
 198
 199 static int git_patch_id_config(const char *var, const char *value,
 200                                const struct config_context *ctx, void *cb)
 201 {
 202         struct patch_id_opts *opts = cb;
 203
 204         if (!strcmp(var, "patchid.stable")) {
 205                 opts->stable = git_config_bool(var, value);
 206                 return 0;
 207         }
 208         if (!strcmp(var, "patchid.verbatim")) {
 209                 opts->verbatim = git_config_bool(var, value);
 210                 return 0;
 211         }
 212
 213         return git_default_config(var, value, ctx, cb);
 214 }
 215
 216 int cmd_patch_id(int argc, const char **argv, const char *prefix)
 217 {
 218         /* if nothing is set, default to unstable */
 219         struct patch_id_opts config = {0, 0};
 220         int opts = 0;
 221         struct option builtin_patch_id_options[] = {
 222                 OPT_CMDMODE(0, "unstable", &opts,
 223                     N_("use the unstable patch-id algorithm"), 1),
 224                 OPT_CMDMODE(0, "stable", &opts,
 225                     N_("use the stable patch-id algorithm"), 2),
 226                 OPT_CMDMODE(0, "verbatim", &opts,
 227                         N_("don't strip whitespace from the patch"), 3),
 228                 OPT_END()
 229         };
 230
 231         git_config(git_patch_id_config, &config);
 232
 233         /* verbatim implies stable */
 234         if (config.verbatim)
 235                 config.stable = 1;
 236
 237         argc = parse_options(argc, argv, prefix, builtin_patch_id_options,
 238                              patch_id_usage, 0);
 239
 240         generate_id_list(opts ? opts > 1 : config.stable,
 241                          opts ? opts == 3 : config.verbatim);
 242         return 0;
 243 }