setup.c

   1 #include "cache.h"
   2
   3 static char *prefix_path(const char *prefix, int len, char *path)
   4 {
   5         char *orig = path;
   6         for (;;) {
   7                 char c;
   8                 if (*path != '.')
   9                         break;
  10                 c = path[1];
  11                 /* "." */
  12                 if (!c) {
  13                         path++;
  14                         break;
  15                 }
  16                 /* "./" */
  17                 if (c == '/') {
  18                         path += 2;
  19                         continue;
  20                 }
  21                 if (c != '.')
  22                         break;
  23                 c = path[2];
  24                 if (!c)
  25                         path += 2;
  26                 else if (c == '/')
  27                         path += 3;
  28                 else
  29                         break;
  30                 /* ".." and "../" */
  31                 /* Remove last component of the prefix */
  32                 do {
  33                         if (!len)
  34                                 die("'%s' is outside repository", orig);
  35                         len--;
  36                 } while (len && prefix[len-1] != '/');
  37                 continue;
  38         }
  39         if (len) {
  40                 int speclen = strlen(path);
  41                 char *n = xmalloc(speclen + len + 1);
  42
  43                 memcpy(n, prefix, len);
  44                 memcpy(n + len, path, speclen+1);
  45                 path = n;
  46         }
  47         return path;
  48 }
  49
  50 const char **get_pathspec(const char *prefix, char **pathspec)
  51 {
  52         char *entry = *pathspec;
  53         char **p;
  54         int prefixlen;
  55
  56         if (!prefix && !entry)
  57                 return NULL;
  58
  59         if (!entry) {
  60                 static const char *spec[2];
  61                 spec[0] = prefix;
  62                 spec[1] = NULL;
  63                 return spec;
  64         }
  65
  66         /* Otherwise we have to re-write the entries.. */
  67         p = pathspec;
  68         prefixlen = prefix ? strlen(prefix) : 0;
  69         do {
  70                 *p = prefix_path(prefix, prefixlen, entry);
  71         } while ((entry = *++p) != NULL);
  72         return (const char **) pathspec;
  73 }
  74
  75 const char *setup_git_directory(void)
  76 {
  77         static char cwd[PATH_MAX+1];
  78         int len, offset;
  79
  80         /*
  81          * If GIT_DIR is set explicitly, we're not going
  82          * to do any discovery
  83          */
  84         if (gitenv(GIT_DIR_ENVIRONMENT))
  85                 return NULL;
  86
  87         if (!getcwd(cwd, sizeof(cwd)) || cwd[0] != '/')
  88                 die("Unable to read current working directory");
  89
  90         offset = len = strlen(cwd);
  91         for (;;) {
  92                 /*
  93                  * We always want to see a .git/refs/ subdirectory
  94                  */
  95                 if (!access(".git/refs/", X_OK)) {
  96                         /*
  97                          * Then we need either a GIT_OBJECT_DIRECTORY define
  98                          * or a .git/objects/ directory
  99                          */
 100                         if (gitenv(DB_ENVIRONMENT) || !access(".git/objects/", X_OK))
 101                                 break;
 102                 }
 103                 chdir("..");
 104                 do {
 105                         if (!offset)
 106                                 die("Not a git repository");
 107                 } while (cwd[--offset] != '/');
 108         }
 109
 110         if (offset == len)
 111                 return NULL;
 112
 113         /* Make "offset" point to past the '/', and add a '/' at the end */
 114         offset++;
 115         cwd[len++] = '/';
 116         cwd[len] = 0;
 117         return cwd + offset;
 118 }