pathspec.c

   1 #include "cache.h"
   2 #include "dir.h"
   3 #include "pathspec.h"
   4
   5 /*
   6  * Finds which of the given pathspecs match items in the index.
   7  *
   8  * For each pathspec, sets the corresponding entry in the seen[] array
   9  * (which should be specs items long, i.e. the same size as pathspec)
  10  * to the nature of the "closest" (i.e. most specific) match found for
  11  * that pathspec in the index, if it was a closer type of match than
  12  * the existing entry.  As an optimization, matching is skipped
  13  * altogether if seen[] already only contains non-zero entries.
  14  *
  15  * If seen[] has not already been written to, it may make sense
  16  * to use find_pathspecs_matching_against_index() instead.
  17  */
  18 void add_pathspec_matches_against_index(const struct pathspec *pathspec,
  19                                         char *seen)
  20 {
  21         int num_unmatched = 0, i;
  22
  23         /*
  24          * Since we are walking the index as if we were walking the directory,
  25          * we have to mark the matched pathspec as seen; otherwise we will
  26          * mistakenly think that the user gave a pathspec that did not match
  27          * anything.
  28          */
  29         for (i = 0; i < pathspec->nr; i++)
  30                 if (!seen[i])
  31                         num_unmatched++;
  32         if (!num_unmatched)
  33                 return;
  34         for (i = 0; i < active_nr; i++) {
  35                 struct cache_entry *ce = active_cache[i];
  36                 match_pathspec_depth(pathspec, ce->name, ce_namelen(ce), 0, seen);
  37         }
  38 }
  39
  40 /*
  41  * Finds which of the given pathspecs match items in the index.
  42  *
  43  * This is a one-shot wrapper around add_pathspec_matches_against_index()
  44  * which allocates, populates, and returns a seen[] array indicating the
  45  * nature of the "closest" (i.e. most specific) matches which each of the
  46  * given pathspecs achieves against all items in the index.
  47  */
  48 char *find_pathspecs_matching_against_index(const struct pathspec *pathspec)
  49 {
  50         char *seen = xcalloc(pathspec->nr, 1);
  51         add_pathspec_matches_against_index(pathspec, seen);
  52         return seen;
  53 }
  54
  55 /*
  56  * Magic pathspec
  57  *
  58  * Possible future magic semantics include stuff like:
  59  *
  60  *      { PATHSPEC_NOGLOB, '!', "noglob" },
  61  *      { PATHSPEC_ICASE, '\0', "icase" },
  62  *      { PATHSPEC_RECURSIVE, '*', "recursive" },
  63  *      { PATHSPEC_REGEXP, '\0', "regexp" },
  64  *
  65  */
  66
  67 static struct pathspec_magic {
  68         unsigned bit;
  69         char mnemonic; /* this cannot be ':'! */
  70         const char *name;
  71 } pathspec_magic[] = {
  72         { PATHSPEC_FROMTOP, '/', "top" },
  73 };
  74
  75 /*
  76  * Take an element of a pathspec and check for magic signatures.
  77  * Append the result to the prefix. Return the magic bitmap.
  78  *
  79  * For now, we only parse the syntax and throw out anything other than
  80  * "top" magic.
  81  *
  82  * NEEDSWORK: This needs to be rewritten when we start migrating
  83  * get_pathspec() users to use the "struct pathspec" interface.  For
  84  * example, a pathspec element may be marked as case-insensitive, but
  85  * the prefix part must always match literally, and a single stupid
  86  * string cannot express such a case.
  87  */
  88 static unsigned prefix_pathspec(struct pathspec_item *item,
  89                                 unsigned *p_short_magic,
  90                                 const char **raw, unsigned flags,
  91                                 const char *prefix, int prefixlen,
  92                                 const char *elt)
  93 {
  94         unsigned magic = 0, short_magic = 0;
  95         const char *copyfrom = elt;
  96         char *match;
  97         int i;
  98
  99         if (elt[0] != ':') {
 100                 ; /* nothing to do */
 101         } else if (elt[1] == '(') {
 102                 /* longhand */
 103                 const char *nextat;
 104                 for (copyfrom = elt + 2;
 105                      *copyfrom && *copyfrom != ')';
 106                      copyfrom = nextat) {
 107                         size_t len = strcspn(copyfrom, ",)");
 108                         if (copyfrom[len] == ',')
 109                                 nextat = copyfrom + len + 1;
 110                         else
 111                                 /* handle ')' and '\0' */
 112                                 nextat = copyfrom + len;
 113                         if (!len)
 114                                 continue;
 115                         for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 116                                 if (strlen(pathspec_magic[i].name) == len &&
 117                                     !strncmp(pathspec_magic[i].name, copyfrom, len)) {
 118                                         magic |= pathspec_magic[i].bit;
 119                                         break;
 120                                 }
 121                         if (ARRAY_SIZE(pathspec_magic) <= i)
 122                                 die(_("Invalid pathspec magic '%.*s' in '%s'"),
 123                                     (int) len, copyfrom, elt);
 124                 }
 125                 if (*copyfrom != ')')
 126                         die(_("Missing ')' at the end of pathspec magic in '%s'"), elt);
 127                 copyfrom++;
 128         } else {
 129                 /* shorthand */
 130                 for (copyfrom = elt + 1;
 131                      *copyfrom && *copyfrom != ':';
 132                      copyfrom++) {
 133                         char ch = *copyfrom;
 134
 135                         if (!is_pathspec_magic(ch))
 136                                 break;
 137                         for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 138                                 if (pathspec_magic[i].mnemonic == ch) {
 139                                         short_magic |= pathspec_magic[i].bit;
 140                                         break;
 141                                 }
 142                         if (ARRAY_SIZE(pathspec_magic) <= i)
 143                                 die(_("Unimplemented pathspec magic '%c' in '%s'"),
 144                                     ch, elt);
 145                 }
 146                 if (*copyfrom == ':')
 147                         copyfrom++;
 148         }
 149
 150         magic |= short_magic;
 151         *p_short_magic = short_magic;
 152
 153         if (magic & PATHSPEC_FROMTOP) {
 154                 match = xstrdup(copyfrom);
 155                 prefixlen = 0;
 156         } else {
 157                 match = prefix_path_gently(prefix, prefixlen, &prefixlen, copyfrom);
 158                 if (!match)
 159                         die(_("%s: '%s' is outside repository"), elt, copyfrom);
 160         }
 161         *raw = item->match = match;
 162         /*
 163          * Prefix the pathspec (keep all magic) and assign to
 164          * original. Useful for passing to another command.
 165          */
 166         if (flags & PATHSPEC_PREFIX_ORIGIN) {
 167                 struct strbuf sb = STRBUF_INIT;
 168                 strbuf_add(&sb, elt, copyfrom - elt);
 169                 strbuf_addstr(&sb, match);
 170                 item->original = strbuf_detach(&sb, NULL);
 171         } else
 172                 item->original = elt;
 173         item->len = strlen(item->match);
 174         item->prefix = prefixlen;
 175
 176         if ((flags & PATHSPEC_STRIP_SUBMODULE_SLASH_CHEAP) &&
 177             (item->len >= 1 && item->match[item->len - 1] == '/') &&
 178             (i = cache_name_pos(item->match, item->len - 1)) >= 0 &&
 179             S_ISGITLINK(active_cache[i]->ce_mode)) {
 180                 item->len--;
 181                 match[item->len] = '\0';
 182         }
 183
 184         if (flags & PATHSPEC_STRIP_SUBMODULE_SLASH_EXPENSIVE)
 185                 for (i = 0; i < active_nr; i++) {
 186                         struct cache_entry *ce = active_cache[i];
 187                         int ce_len = ce_namelen(ce);
 188
 189                         if (!S_ISGITLINK(ce->ce_mode))
 190                                 continue;
 191
 192                         if (item->len <= ce_len || match[ce_len] != '/' ||
 193                             memcmp(ce->name, match, ce_len))
 194                                 continue;
 195                         if (item->len == ce_len + 1) {
 196                                 /* strip trailing slash */
 197                                 item->len--;
 198                                 match[item->len] = '\0';
 199                         } else
 200                                 die (_("Pathspec '%s' is in submodule '%.*s'"),
 201                                      elt, ce_len, ce->name);
 202                 }
 203
 204         if (limit_pathspec_to_literal())
 205                 item->nowildcard_len = item->len;
 206         else {
 207                 item->nowildcard_len = simple_length(item->match);
 208                 if (item->nowildcard_len < prefixlen)
 209                         item->nowildcard_len = prefixlen;
 210         }
 211         item->flags = 0;
 212         if (item->nowildcard_len < item->len &&
 213             item->match[item->nowildcard_len] == '*' &&
 214             no_wildcard(item->match + item->nowildcard_len + 1))
 215                 item->flags |= PATHSPEC_ONESTAR;
 216
 217         /* sanity checks, pathspec matchers assume these are sane */
 218         assert(item->nowildcard_len <= item->len &&
 219                item->prefix         <= item->len);
 220         return magic;
 221 }
 222
 223 static int pathspec_item_cmp(const void *a_, const void *b_)
 224 {
 225         struct pathspec_item *a, *b;
 226
 227         a = (struct pathspec_item *)a_;
 228         b = (struct pathspec_item *)b_;
 229         return strcmp(a->match, b->match);
 230 }
 231
 232 static void NORETURN unsupported_magic(const char *pattern,
 233                                        unsigned magic,
 234                                        unsigned short_magic)
 235 {
 236         struct strbuf sb = STRBUF_INIT;
 237         int i, n;
 238         for (n = i = 0; i < ARRAY_SIZE(pathspec_magic); i++) {
 239                 const struct pathspec_magic *m = pathspec_magic + i;
 240                 if (!(magic & m->bit))
 241                         continue;
 242                 if (sb.len)
 243                         strbuf_addstr(&sb, " ");
 244                 if (short_magic & m->bit)
 245                         strbuf_addf(&sb, "'%c'", m->mnemonic);
 246                 else
 247                         strbuf_addf(&sb, "'%s'", m->name);
 248                 n++;
 249         }
 250         /*
 251          * We may want to substitute "this command" with a command
 252          * name. E.g. when add--interactive dies when running
 253          * "checkout -p"
 254          */
 255         die(_("%s: pathspec magic not supported by this command: %s"),
 256             pattern, sb.buf);
 257 }
 258
 259 /*
 260  * Given command line arguments and a prefix, convert the input to
 261  * pathspec. die() if any magic in magic_mask is used.
 262  */
 263 void parse_pathspec(struct pathspec *pathspec,
 264                     unsigned magic_mask, unsigned flags,
 265                     const char *prefix, const char **argv)
 266 {
 267         struct pathspec_item *item;
 268         const char *entry = argv ? *argv : NULL;
 269         int i, n, prefixlen;
 270
 271         memset(pathspec, 0, sizeof(*pathspec));
 272
 273         if (flags & PATHSPEC_MAXDEPTH_VALID)
 274                 pathspec->magic |= PATHSPEC_MAXDEPTH;
 275
 276         /* No arguments, no prefix -> no pathspec */
 277         if (!entry && !prefix)
 278                 return;
 279
 280         if ((flags & PATHSPEC_PREFER_CWD) &&
 281             (flags & PATHSPEC_PREFER_FULL))
 282                 die("BUG: PATHSPEC_PREFER_CWD and PATHSPEC_PREFER_FULL are incompatible");
 283
 284         /* No arguments with prefix -> prefix pathspec */
 285         if (!entry) {
 286                 static const char *raw[2];
 287
 288                 if (flags & PATHSPEC_PREFER_FULL)
 289                         return;
 290
 291                 if (!(flags & PATHSPEC_PREFER_CWD))
 292                         die("BUG: PATHSPEC_PREFER_CWD requires arguments");
 293
 294                 pathspec->items = item = xmalloc(sizeof(*item));
 295                 memset(item, 0, sizeof(*item));
 296                 item->match = prefix;
 297                 item->original = prefix;
 298                 item->nowildcard_len = item->len = strlen(prefix);
 299                 item->prefix = item->len;
 300                 raw[0] = prefix;
 301                 raw[1] = NULL;
 302                 pathspec->nr = 1;
 303                 pathspec->_raw = raw;
 304                 return;
 305         }
 306
 307         n = 0;
 308         while (argv[n])
 309                 n++;
 310
 311         pathspec->nr = n;
 312         pathspec->items = item = xmalloc(sizeof(*item) * n);
 313         pathspec->_raw = argv;
 314         prefixlen = prefix ? strlen(prefix) : 0;
 315
 316         for (i = 0; i < n; i++) {
 317                 unsigned short_magic;
 318                 entry = argv[i];
 319
 320                 item[i].magic = prefix_pathspec(item + i, &short_magic,
 321                                                 argv + i, flags,
 322                                                 prefix, prefixlen, entry);
 323                 if (item[i].magic & magic_mask)
 324                         unsupported_magic(entry,
 325                                           item[i].magic & magic_mask,
 326                                           short_magic);
 327
 328                 if ((flags & PATHSPEC_SYMLINK_LEADING_PATH) &&
 329                     has_symlink_leading_path(item[i].match, item[i].len)) {
 330                         die(_("pathspec '%s' is beyond a symbolic link"), entry);
 331                 }
 332
 333                 if (item[i].nowildcard_len < item[i].len)
 334                         pathspec->has_wildcard = 1;
 335                 pathspec->magic |= item[i].magic;
 336         }
 337
 338
 339         if (pathspec->magic & PATHSPEC_MAXDEPTH) {
 340                 if (flags & PATHSPEC_KEEP_ORDER)
 341                         die("BUG: PATHSPEC_MAXDEPTH_VALID and PATHSPEC_KEEP_ORDER are incompatible");
 342                 qsort(pathspec->items, pathspec->nr,
 343                       sizeof(struct pathspec_item), pathspec_item_cmp);
 344         }
 345 }
 346
 347 /*
 348  * N.B. get_pathspec() is deprecated in favor of the "struct pathspec"
 349  * based interface - see pathspec.c:parse_pathspec().
 350  *
 351  * Arguments:
 352  *  - prefix - a path relative to the root of the working tree
 353  *  - pathspec - a list of paths underneath the prefix path
 354  *
 355  * Iterates over pathspec, prepending each path with prefix,
 356  * and return the resulting list.
 357  *
 358  * If pathspec is empty, return a singleton list containing prefix.
 359  *
 360  * If pathspec and prefix are both empty, return an empty list.
 361  *
 362  * This is typically used by built-in commands such as add.c, in order
 363  * to normalize argv arguments provided to the built-in into a list of
 364  * paths to process, all relative to the root of the working tree.
 365  */
 366 const char **get_pathspec(const char *prefix, const char **pathspec)
 367 {
 368         struct pathspec ps;
 369         parse_pathspec(&ps,
 370                        PATHSPEC_ALL_MAGIC & ~PATHSPEC_FROMTOP,
 371                        PATHSPEC_PREFER_CWD,
 372                        prefix, pathspec);
 373         return ps._raw;
 374 }
 375
 376 void copy_pathspec(struct pathspec *dst, const struct pathspec *src)
 377 {
 378         *dst = *src;
 379         dst->items = xmalloc(sizeof(struct pathspec_item) * dst->nr);
 380         memcpy(dst->items, src->items,
 381                sizeof(struct pathspec_item) * dst->nr);
 382 }
 383
 384 void free_pathspec(struct pathspec *pathspec)
 385 {
 386         free(pathspec->items);
 387         pathspec->items = NULL;
 388 }