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  * Check the index to see whether path refers to a submodule, or
  62  * something inside a submodule.  If the former, returns the path with
  63  * any trailing slash stripped.  If the latter, dies with an error
  64  * message.
  65  */
  66 const char *check_path_for_gitlink(const char *path)
  67 {
  68         int i, path_len = strlen(path);
  69         for (i = 0; i < active_nr; i++) {
  70                 struct cache_entry *ce = active_cache[i];
  71                 if (S_ISGITLINK(ce->ce_mode)) {
  72                         int ce_len = ce_namelen(ce);
  73                         if (path_len <= ce_len || path[ce_len] != '/' ||
  74                             memcmp(ce->name, path, ce_len))
  75                                 /* path does not refer to this
  76                                  * submodule or anything inside it */
  77                                 continue;
  78                         if (path_len == ce_len + 1) {
  79                                 /* path refers to submodule;
  80                                  * strip trailing slash */
  81                                 return xstrndup(ce->name, ce_len);
  82                         } else {
  83                                 die (_("Path '%s' is in submodule '%.*s'"),
  84                                      path, ce_len, ce->name);
  85                         }
  86                 }
  87         }
  88         return path;
  89 }
  90
  91 /*
  92  * Dies if the given path refers to a file inside a symlinked
  93  * directory in the index.
  94  */
  95 void die_if_path_beyond_symlink(const char *path, const char *prefix)
  96 {
  97         if (has_symlink_leading_path(path, strlen(path))) {
  98                 int len = prefix ? strlen(prefix) : 0;
  99                 die(_("'%s' is beyond a symbolic link"), path + len);
 100         }
 101 }
 102
 103 /*
 104  * Magic pathspec
 105  *
 106  * NEEDSWORK: These need to be moved to dir.h or even to a new
 107  * pathspec.h when we restructure get_pathspec() users to use the
 108  * "struct pathspec" interface.
 109  *
 110  * Possible future magic semantics include stuff like:
 111  *
 112  *      { PATHSPEC_NOGLOB, '!', "noglob" },
 113  *      { PATHSPEC_ICASE, '\0', "icase" },
 114  *      { PATHSPEC_RECURSIVE, '*', "recursive" },
 115  *      { PATHSPEC_REGEXP, '\0', "regexp" },
 116  *
 117  */
 118 #define PATHSPEC_FROMTOP    (1<<0)
 119
 120 static struct pathspec_magic {
 121         unsigned bit;
 122         char mnemonic; /* this cannot be ':'! */
 123         const char *name;
 124 } pathspec_magic[] = {
 125         { PATHSPEC_FROMTOP, '/', "top" },
 126 };
 127
 128 /*
 129  * Take an element of a pathspec and check for magic signatures.
 130  * Append the result to the prefix.
 131  *
 132  * For now, we only parse the syntax and throw out anything other than
 133  * "top" magic.
 134  *
 135  * NEEDSWORK: This needs to be rewritten when we start migrating
 136  * get_pathspec() users to use the "struct pathspec" interface.  For
 137  * example, a pathspec element may be marked as case-insensitive, but
 138  * the prefix part must always match literally, and a single stupid
 139  * string cannot express such a case.
 140  */
 141 static const char *prefix_pathspec(const char *prefix, int prefixlen, const char *elt)
 142 {
 143         unsigned magic = 0;
 144         const char *copyfrom = elt;
 145         int i;
 146
 147         if (elt[0] != ':') {
 148                 ; /* nothing to do */
 149         } else if (elt[1] == '(') {
 150                 /* longhand */
 151                 const char *nextat;
 152                 for (copyfrom = elt + 2;
 153                      *copyfrom && *copyfrom != ')';
 154                      copyfrom = nextat) {
 155                         size_t len = strcspn(copyfrom, ",)");
 156                         if (copyfrom[len] == ',')
 157                                 nextat = copyfrom + len + 1;
 158                         else
 159                                 /* handle ')' and '\0' */
 160                                 nextat = copyfrom + len;
 161                         if (!len)
 162                                 continue;
 163                         for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 164                                 if (strlen(pathspec_magic[i].name) == len &&
 165                                     !strncmp(pathspec_magic[i].name, copyfrom, len)) {
 166                                         magic |= pathspec_magic[i].bit;
 167                                         break;
 168                                 }
 169                         if (ARRAY_SIZE(pathspec_magic) <= i)
 170                                 die(_("Invalid pathspec magic '%.*s' in '%s'"),
 171                                     (int) len, copyfrom, elt);
 172                 }
 173                 if (*copyfrom != ')')
 174                         die(_("Missing ')' at the end of pathspec magic in '%s'"), elt);
 175                 copyfrom++;
 176         } else {
 177                 /* shorthand */
 178                 for (copyfrom = elt + 1;
 179                      *copyfrom && *copyfrom != ':';
 180                      copyfrom++) {
 181                         char ch = *copyfrom;
 182
 183                         if (!is_pathspec_magic(ch))
 184                                 break;
 185                         for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
 186                                 if (pathspec_magic[i].mnemonic == ch) {
 187                                         magic |= pathspec_magic[i].bit;
 188                                         break;
 189                                 }
 190                         if (ARRAY_SIZE(pathspec_magic) <= i)
 191                                 die(_("Unimplemented pathspec magic '%c' in '%s'"),
 192                                     ch, elt);
 193                 }
 194                 if (*copyfrom == ':')
 195                         copyfrom++;
 196         }
 197
 198         if (magic & PATHSPEC_FROMTOP)
 199                 return xstrdup(copyfrom);
 200         else
 201                 return prefix_path(prefix, prefixlen, copyfrom);
 202 }
 203
 204 /*
 205  * N.B. get_pathspec() is deprecated in favor of the "struct pathspec"
 206  * based interface - see pathspec_magic above.
 207  *
 208  * Arguments:
 209  *  - prefix - a path relative to the root of the working tree
 210  *  - pathspec - a list of paths underneath the prefix path
 211  *
 212  * Iterates over pathspec, prepending each path with prefix,
 213  * and return the resulting list.
 214  *
 215  * If pathspec is empty, return a singleton list containing prefix.
 216  *
 217  * If pathspec and prefix are both empty, return an empty list.
 218  *
 219  * This is typically used by built-in commands such as add.c, in order
 220  * to normalize argv arguments provided to the built-in into a list of
 221  * paths to process, all relative to the root of the working tree.
 222  */
 223 const char **get_pathspec(const char *prefix, const char **pathspec)
 224 {
 225         const char *entry = *pathspec;
 226         const char **src, **dst;
 227         int prefixlen;
 228
 229         if (!prefix && !entry)
 230                 return NULL;
 231
 232         if (!entry) {
 233                 static const char *spec[2];
 234                 spec[0] = prefix;
 235                 spec[1] = NULL;
 236                 return spec;
 237         }
 238
 239         /* Otherwise we have to re-write the entries.. */
 240         src = pathspec;
 241         dst = pathspec;
 242         prefixlen = prefix ? strlen(prefix) : 0;
 243         while (*src) {
 244                 *(dst++) = prefix_pathspec(prefix, prefixlen, *src);
 245                 src++;
 246         }
 247         *dst = NULL;
 248         if (!*pathspec)
 249                 return NULL;
 250         return pathspec;
 251 }