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         else
 156                 match = prefix_path(prefix, prefixlen, copyfrom);
 157         *raw = item->match = match;
 158         /*
 159          * Prefix the pathspec (keep all magic) and assign to
 160          * original. Useful for passing to another command.
 161          */
 162         if (flags & PATHSPEC_PREFIX_ORIGIN) {
 163                 struct strbuf sb = STRBUF_INIT;
 164                 strbuf_add(&sb, elt, copyfrom - elt);
 165                 strbuf_addstr(&sb, match);
 166                 item->original = strbuf_detach(&sb, NULL);
 167         } else
 168                 item->original = elt;
 169         item->len = strlen(item->match);
 170
 171         if ((flags & PATHSPEC_STRIP_SUBMODULE_SLASH_CHEAP) &&
 172             (item->len >= 1 && item->match[item->len - 1] == '/') &&
 173             (i = cache_name_pos(item->match, item->len - 1)) >= 0 &&
 174             S_ISGITLINK(active_cache[i]->ce_mode)) {
 175                 item->len--;
 176                 match[item->len] = '\0';
 177         }
 178
 179         if (flags & PATHSPEC_STRIP_SUBMODULE_SLASH_EXPENSIVE)
 180                 for (i = 0; i < active_nr; i++) {
 181                         struct cache_entry *ce = active_cache[i];
 182                         int ce_len = ce_namelen(ce);
 183
 184                         if (!S_ISGITLINK(ce->ce_mode))
 185                                 continue;
 186
 187                         if (item->len <= ce_len || match[ce_len] != '/' ||
 188                             memcmp(ce->name, match, ce_len))
 189                                 continue;
 190                         if (item->len == ce_len + 1) {
 191                                 /* strip trailing slash */
 192                                 item->len--;
 193                                 match[item->len] = '\0';
 194                         } else
 195                                 die (_("Pathspec '%s' is in submodule '%.*s'"),
 196                                      elt, ce_len, ce->name);
 197                 }
 198
 199         if (limit_pathspec_to_literal())
 200                 item->nowildcard_len = item->len;
 201         else
 202                 item->nowildcard_len = simple_length(item->match);
 203         item->flags = 0;
 204         if (item->nowildcard_len < item->len &&
 205             item->match[item->nowildcard_len] == '*' &&
 206             no_wildcard(item->match + item->nowildcard_len + 1))
 207                 item->flags |= PATHSPEC_ONESTAR;
 208         return magic;
 209 }
 210
 211 static int pathspec_item_cmp(const void *a_, const void *b_)
 212 {
 213         struct pathspec_item *a, *b;
 214
 215         a = (struct pathspec_item *)a_;
 216         b = (struct pathspec_item *)b_;
 217         return strcmp(a->match, b->match);
 218 }
 219
 220 static void NORETURN unsupported_magic(const char *pattern,
 221                                        unsigned magic,
 222                                        unsigned short_magic)
 223 {
 224         struct strbuf sb = STRBUF_INIT;
 225         int i, n;
 226         for (n = i = 0; i < ARRAY_SIZE(pathspec_magic); i++) {
 227                 const struct pathspec_magic *m = pathspec_magic + i;
 228                 if (!(magic & m->bit))
 229                         continue;
 230                 if (sb.len)
 231                         strbuf_addstr(&sb, " ");
 232                 if (short_magic & m->bit)
 233                         strbuf_addf(&sb, "'%c'", m->mnemonic);
 234                 else
 235                         strbuf_addf(&sb, "'%s'", m->name);
 236                 n++;
 237         }
 238         /*
 239          * We may want to substitute "this command" with a command
 240          * name. E.g. when add--interactive dies when running
 241          * "checkout -p"
 242          */
 243         die(_("%s: pathspec magic not supported by this command: %s"),
 244             pattern, sb.buf);
 245 }
 246
 247 /*
 248  * Given command line arguments and a prefix, convert the input to
 249  * pathspec. die() if any magic in magic_mask is used.
 250  */
 251 void parse_pathspec(struct pathspec *pathspec,
 252                     unsigned magic_mask, unsigned flags,
 253                     const char *prefix, const char **argv)
 254 {
 255         struct pathspec_item *item;
 256         const char *entry = argv ? *argv : NULL;
 257         int i, n, prefixlen;
 258
 259         memset(pathspec, 0, sizeof(*pathspec));
 260
 261         if (flags & PATHSPEC_MAXDEPTH_VALID)
 262                 pathspec->magic |= PATHSPEC_MAXDEPTH;
 263
 264         /* No arguments, no prefix -> no pathspec */
 265         if (!entry && !prefix)
 266                 return;
 267
 268         if ((flags & PATHSPEC_PREFER_CWD) &&
 269             (flags & PATHSPEC_PREFER_FULL))
 270                 die("BUG: PATHSPEC_PREFER_CWD and PATHSPEC_PREFER_FULL are incompatible");
 271
 272         /* No arguments with prefix -> prefix pathspec */
 273         if (!entry) {
 274                 static const char *raw[2];
 275
 276                 if (flags & PATHSPEC_PREFER_FULL)
 277                         return;
 278
 279                 if (!(flags & PATHSPEC_PREFER_CWD))
 280                         die("BUG: PATHSPEC_PREFER_CWD requires arguments");
 281
 282                 pathspec->items = item = xmalloc(sizeof(*item));
 283                 memset(item, 0, sizeof(*item));
 284                 item->match = prefix;
 285                 item->original = prefix;
 286                 item->nowildcard_len = item->len = strlen(prefix);
 287                 raw[0] = prefix;
 288                 raw[1] = NULL;
 289                 pathspec->nr = 1;
 290                 pathspec->_raw = raw;
 291                 return;
 292         }
 293
 294         n = 0;
 295         while (argv[n])
 296                 n++;
 297
 298         pathspec->nr = n;
 299         pathspec->items = item = xmalloc(sizeof(*item) * n);
 300         pathspec->_raw = argv;
 301         prefixlen = prefix ? strlen(prefix) : 0;
 302
 303         for (i = 0; i < n; i++) {
 304                 unsigned short_magic;
 305                 entry = argv[i];
 306
 307                 item[i].magic = prefix_pathspec(item + i, &short_magic,
 308                                                 argv + i, flags,
 309                                                 prefix, prefixlen, entry);
 310                 if (item[i].magic & magic_mask)
 311                         unsupported_magic(entry,
 312                                           item[i].magic & magic_mask,
 313                                           short_magic);
 314
 315                 if ((flags & PATHSPEC_SYMLINK_LEADING_PATH) &&
 316                     has_symlink_leading_path(item[i].match, item[i].len)) {
 317                         die(_("pathspec '%s' is beyond a symbolic link"), entry);
 318                 }
 319
 320                 if (item[i].nowildcard_len < item[i].len)
 321                         pathspec->has_wildcard = 1;
 322                 pathspec->magic |= item[i].magic;
 323         }
 324
 325
 326         if (pathspec->magic & PATHSPEC_MAXDEPTH) {
 327                 if (flags & PATHSPEC_KEEP_ORDER)
 328                         die("BUG: PATHSPEC_MAXDEPTH_VALID and PATHSPEC_KEEP_ORDER are incompatible");
 329                 qsort(pathspec->items, pathspec->nr,
 330                       sizeof(struct pathspec_item), pathspec_item_cmp);
 331         }
 332 }
 333
 334 /*
 335  * N.B. get_pathspec() is deprecated in favor of the "struct pathspec"
 336  * based interface - see pathspec.c:parse_pathspec().
 337  *
 338  * Arguments:
 339  *  - prefix - a path relative to the root of the working tree
 340  *  - pathspec - a list of paths underneath the prefix path
 341  *
 342  * Iterates over pathspec, prepending each path with prefix,
 343  * and return the resulting list.
 344  *
 345  * If pathspec is empty, return a singleton list containing prefix.
 346  *
 347  * If pathspec and prefix are both empty, return an empty list.
 348  *
 349  * This is typically used by built-in commands such as add.c, in order
 350  * to normalize argv arguments provided to the built-in into a list of
 351  * paths to process, all relative to the root of the working tree.
 352  */
 353 const char **get_pathspec(const char *prefix, const char **pathspec)
 354 {
 355         struct pathspec ps;
 356         parse_pathspec(&ps,
 357                        PATHSPEC_ALL_MAGIC & ~PATHSPEC_FROMTOP,
 358                        PATHSPEC_PREFER_CWD,
 359                        prefix, pathspec);
 360         return ps._raw;
 361 }
 362
 363 void copy_pathspec(struct pathspec *dst, const struct pathspec *src)
 364 {
 365         *dst = *src;
 366         dst->items = xmalloc(sizeof(struct pathspec_item) * dst->nr);
 367         memcpy(dst->items, src->items,
 368                sizeof(struct pathspec_item) * dst->nr);
 369 }
 370
 371 void free_pathspec(struct pathspec *pathspec)
 372 {
 373         free(pathspec->items);
 374         pathspec->items = NULL;
 375 }