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 char **pathspec,
  19                                         char *seen, int specs)
  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 < specs; 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(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 char **pathspec)
  49 {
  50         char *seen;
  51         int i;
  52
  53         for (i = 0; pathspec[i];  i++)
  54                 ; /* just counting */
  55         seen = xcalloc(i, 1);
  56         add_pathspec_matches_against_index(pathspec, seen, i);
  57         return seen;
  58 }
  59
  60 /*
  61  * Magic pathspec
  62  *
  63  * Possible future magic semantics include stuff like:
  64  *
  65  *      { PATHSPEC_NOGLOB, '!', "noglob" },
  66  *      { PATHSPEC_ICASE, '\0', "icase" },
  67  *      { PATHSPEC_RECURSIVE, '*', "recursive" },
  68  *      { PATHSPEC_REGEXP, '\0', "regexp" },
  69  *
  70  */
  71
  72 static struct pathspec_magic {
  73         unsigned bit;
  74         char mnemonic; /* this cannot be ':'! */
  75         const char *name;
  76 } pathspec_magic[] = {
  77         { PATHSPEC_FROMTOP, '/', "top" },
  78 };
  79
  80 /*
  81  * Take an element of a pathspec and check for magic signatures.
  82  * Append the result to the prefix. Return the magic bitmap.
  83  *
  84  * For now, we only parse the syntax and throw out anything other than
  85  * "top" magic.
  86  *
  87  * NEEDSWORK: This needs to be rewritten when we start migrating
  88  * get_pathspec() users to use the "struct pathspec" interface.  For
  89  * example, a pathspec element may be marked as case-insensitive, but
  90  * the prefix part must always match literally, and a single stupid
  91  * string cannot express such a case.
  92  */
  93 static unsigned prefix_pathspec(struct pathspec_item *item,
  94                                 unsigned *p_short_magic,
  95                                 const char **raw, unsigned flags,
  96                                 const char *prefix, int prefixlen,
  97                                 const char *elt)
  98 {
  99         unsigned magic = 0, short_magic = 0;
 100         const char *copyfrom = elt;
 101         char *match;
 102         int i;
 103
 104         if (elt[0] != ':') {
 105                 ; /* nothing to do */
 106         } else if (elt[1] == '(') {
 107                 /* longhand */
 108                 const char *nextat;
 109                 for (copyfrom = elt + 2;
 110                      *copyfrom && *copyfrom != ')';
 111                      copyfrom = nextat) {
 112                         size_t len = strcspn(copyfrom, ",)");
 113                         if (copyfrom[len] == ',')
 114                                 nextat = copyfrom + len + 1;
 115                         else
 116                                 /* handle ')' and '\0' */
 117                                 nextat = copyfrom + len;
 118                         if (!len)
 119                                 continue;
 120                         for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 121                                 if (strlen(pathspec_magic[i].name) == len &&
 122                                     !strncmp(pathspec_magic[i].name, copyfrom, len)) {
 123                                         magic |= pathspec_magic[i].bit;
 124                                         break;
 125                                 }
 126                         if (ARRAY_SIZE(pathspec_magic) <= i)
 127                                 die(_("Invalid pathspec magic '%.*s' in '%s'"),
 128                                     (int) len, copyfrom, elt);
 129                 }
 130                 if (*copyfrom != ')')
 131                         die(_("Missing ')' at the end of pathspec magic in '%s'"), elt);
 132                 copyfrom++;
 133         } else {
 134                 /* shorthand */
 135                 for (copyfrom = elt + 1;
 136                      *copyfrom && *copyfrom != ':';
 137                      copyfrom++) {
 138                         char ch = *copyfrom;
 139
 140                         if (!is_pathspec_magic(ch))
 141                                 break;
 142                         for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 143                                 if (pathspec_magic[i].mnemonic == ch) {
 144                                         short_magic |= pathspec_magic[i].bit;
 145                                         break;
 146                                 }
 147                         if (ARRAY_SIZE(pathspec_magic) <= i)
 148                                 die(_("Unimplemented pathspec magic '%c' in '%s'"),
 149                                     ch, elt);
 150                 }
 151                 if (*copyfrom == ':')
 152                         copyfrom++;
 153         }
 154
 155         magic |= short_magic;
 156         *p_short_magic = short_magic;
 157
 158         if (magic & PATHSPEC_FROMTOP)
 159                 match = xstrdup(copyfrom);
 160         else
 161                 match = prefix_path(prefix, prefixlen, copyfrom);
 162         *raw = item->match = match;
 163         /*
 164          * Prefix the pathspec (keep all magic) and assign to
 165          * original. Useful for passing to another command.
 166          */
 167         if (flags & PATHSPEC_PREFIX_ORIGIN) {
 168                 struct strbuf sb = STRBUF_INIT;
 169                 strbuf_add(&sb, elt, copyfrom - elt);
 170                 strbuf_addstr(&sb, match);
 171                 item->original = strbuf_detach(&sb, NULL);
 172         } else
 173                 item->original = elt;
 174         item->len = strlen(item->match);
 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         item->flags = 0;
 209         if (item->nowildcard_len < item->len &&
 210             item->match[item->nowildcard_len] == '*' &&
 211             no_wildcard(item->match + item->nowildcard_len + 1))
 212                 item->flags |= PATHSPEC_ONESTAR;
 213         return magic;
 214 }
 215
 216 static int pathspec_item_cmp(const void *a_, const void *b_)
 217 {
 218         struct pathspec_item *a, *b;
 219
 220         a = (struct pathspec_item *)a_;
 221         b = (struct pathspec_item *)b_;
 222         return strcmp(a->match, b->match);
 223 }
 224
 225 static void NORETURN unsupported_magic(const char *pattern,
 226                                        unsigned magic,
 227                                        unsigned short_magic)
 228 {
 229         struct strbuf sb = STRBUF_INIT;
 230         int i, n;
 231         for (n = i = 0; i < ARRAY_SIZE(pathspec_magic); i++) {
 232                 const struct pathspec_magic *m = pathspec_magic + i;
 233                 if (!(magic & m->bit))
 234                         continue;
 235                 if (sb.len)
 236                         strbuf_addstr(&sb, " ");
 237                 if (short_magic & m->bit)
 238                         strbuf_addf(&sb, "'%c'", m->mnemonic);
 239                 else
 240                         strbuf_addf(&sb, "'%s'", m->name);
 241                 n++;
 242         }
 243         /*
 244          * We may want to substitute "this command" with a command
 245          * name. E.g. when add--interactive dies when running
 246          * "checkout -p"
 247          */
 248         die(_("%s: pathspec magic not supported by this command: %s"),
 249             pattern, sb.buf);
 250 }
 251
 252 /*
 253  * Given command line arguments and a prefix, convert the input to
 254  * pathspec. die() if any magic in magic_mask is used.
 255  */
 256 void parse_pathspec(struct pathspec *pathspec,
 257                     unsigned magic_mask, unsigned flags,
 258                     const char *prefix, const char **argv)
 259 {
 260         struct pathspec_item *item;
 261         const char *entry = argv ? *argv : NULL;
 262         int i, n, prefixlen;
 263
 264         memset(pathspec, 0, sizeof(*pathspec));
 265
 266         if (flags & PATHSPEC_MAXDEPTH_VALID)
 267                 pathspec->magic |= PATHSPEC_MAXDEPTH;
 268
 269         /* No arguments, no prefix -> no pathspec */
 270         if (!entry && !prefix)
 271                 return;
 272
 273         if ((flags & PATHSPEC_PREFER_CWD) &&
 274             (flags & PATHSPEC_PREFER_FULL))
 275                 die("BUG: PATHSPEC_PREFER_CWD and PATHSPEC_PREFER_FULL are incompatible");
 276
 277         /* No arguments with prefix -> prefix pathspec */
 278         if (!entry) {
 279                 static const char *raw[2];
 280
 281                 if (flags & PATHSPEC_PREFER_FULL)
 282                         return;
 283
 284                 if (!(flags & PATHSPEC_PREFER_CWD))
 285                         die("BUG: PATHSPEC_PREFER_CWD requires arguments");
 286
 287                 pathspec->items = item = xmalloc(sizeof(*item));
 288                 memset(item, 0, sizeof(*item));
 289                 item->match = prefix;
 290                 item->original = prefix;
 291                 item->nowildcard_len = item->len = strlen(prefix);
 292                 raw[0] = prefix;
 293                 raw[1] = NULL;
 294                 pathspec->nr = 1;
 295                 pathspec->raw = raw;
 296                 return;
 297         }
 298
 299         n = 0;
 300         while (argv[n])
 301                 n++;
 302
 303         pathspec->nr = n;
 304         pathspec->items = item = xmalloc(sizeof(*item) * n);
 305         pathspec->raw = argv;
 306         prefixlen = prefix ? strlen(prefix) : 0;
 307
 308         for (i = 0; i < n; i++) {
 309                 unsigned short_magic;
 310                 entry = argv[i];
 311
 312                 item[i].magic = prefix_pathspec(item + i, &short_magic,
 313                                                 argv + i, flags,
 314                                                 prefix, prefixlen, entry);
 315                 if (item[i].magic & magic_mask)
 316                         unsupported_magic(entry,
 317                                           item[i].magic & magic_mask,
 318                                           short_magic);
 319
 320                 if ((flags & PATHSPEC_SYMLINK_LEADING_PATH) &&
 321                     has_symlink_leading_path(item[i].match, item[i].len)) {
 322                         die(_("pathspec '%s' is beyond a symbolic link"), entry);
 323                 }
 324
 325                 if (item[i].nowildcard_len < item[i].len)
 326                         pathspec->has_wildcard = 1;
 327                 pathspec->magic |= item[i].magic;
 328         }
 329
 330
 331         if (pathspec->magic & PATHSPEC_MAXDEPTH) {
 332                 if (flags & PATHSPEC_KEEP_ORDER)
 333                         die("BUG: PATHSPEC_MAXDEPTH_VALID and PATHSPEC_KEEP_ORDER are incompatible");
 334                 qsort(pathspec->items, pathspec->nr,
 335                       sizeof(struct pathspec_item), pathspec_item_cmp);
 336         }
 337 }
 338
 339 /*
 340  * N.B. get_pathspec() is deprecated in favor of the "struct pathspec"
 341  * based interface - see pathspec.c:parse_pathspec().
 342  *
 343  * Arguments:
 344  *  - prefix - a path relative to the root of the working tree
 345  *  - pathspec - a list of paths underneath the prefix path
 346  *
 347  * Iterates over pathspec, prepending each path with prefix,
 348  * and return the resulting list.
 349  *
 350  * If pathspec is empty, return a singleton list containing prefix.
 351  *
 352  * If pathspec and prefix are both empty, return an empty list.
 353  *
 354  * This is typically used by built-in commands such as add.c, in order
 355  * to normalize argv arguments provided to the built-in into a list of
 356  * paths to process, all relative to the root of the working tree.
 357  */
 358 const char **get_pathspec(const char *prefix, const char **pathspec)
 359 {
 360         struct pathspec ps;
 361         parse_pathspec(&ps,
 362                        PATHSPEC_ALL_MAGIC & ~PATHSPEC_FROMTOP,
 363                        PATHSPEC_PREFER_CWD,
 364                        prefix, pathspec);
 365         return ps.raw;
 366 }
 367
 368 void copy_pathspec(struct pathspec *dst, const struct pathspec *src)
 369 {
 370         *dst = *src;
 371         dst->items = xmalloc(sizeof(struct pathspec_item) * dst->nr);
 372         memcpy(dst->items, src->items,
 373                sizeof(struct pathspec_item) * dst->nr);
 374 }