libgit-thin/ltrepo.c

   1 /**
   2  * @file
   3  *
   4  * Repository handling functions.
   5  *
   6  * Luiz Fernando N. Capitulino
   7  * <lcapitulino@gmail.com>
   8  */
   9 #include <stdlib.h>
  10 #include <unistd.h>
  11 #include <errno.h>
  12
  13 #include <cache.h>
  14
  15 #include "ltrepo.h"
  16
  17 /**
  18  * Open a GIT repository.
  19  *
  20  * This function must be called before anything else, note that it
  21  * does change the process' current working directory.
  22  *
  23  * \param path relative or absolute repository's path
  24  *
  25  * \returns 0 on success, -1 otherwise.
  26  */
  27 int git_repo_open(const char *path)
  28 {
  29         int err;
  30
  31         if (!path) {
  32                 errno = EINVAL;
  33                 return -1;
  34         }
  35
  36         err = chdir(path);
  37         if (err)
  38                 return -1;
  39
  40         return git_config(git_default_config);
  41 }
  42
  43 /**
  44  * Translate a repository's 'ref' into a SHA1
  45  *
  46  * \param ref ref to be translated
  47  * \param sha1 pointer to a 20-byte array to return the SHA1 into
  48  *
  49  * \returns 0 on success, -1 on error.
  50  */
  51 int git_repo_translate_ref(const char *ref, unsigned char *sha1)
  52 {
  53         if (!ref || !sha1) {
  54                 errno = EINVAL;
  55                 return -1;
  56         }
  57
  58         return get_sha1(ref, sha1);
  59 }
  60
  61 /**
  62  * Get repository's HEAD SHA1
  63  *
  64  * \param sha1 pointer to a 20-byte array to return the HEAD
  65  *             SHA1 into
  66  *
  67  * \returns 0 on success, -1 on error.
  68  */
  69 int git_repo_head(unsigned char *sha1)
  70 {
  71         return git_repo_translate_ref("HEAD", sha1);
  72 }
  73
  74 static int repo_read_object(unsigned char *sha1, int type,
  75                             void **buf, size_t *size)
  76 {
  77         void *p;
  78         int mtype;
  79         unsigned long msize;
  80
  81         if (!sha1 || (!buf && !size))
  82                 goto out_err;
  83
  84         p = read_sha1_file(sha1, &mtype, &msize);
  85         if (!p)
  86                 return -1;
  87
  88         if (mtype != type) {
  89                 free(p);
  90                 goto out_err;
  91         }
  92
  93         if (buf)
  94                 *buf = p;
  95         if (size)
  96                 *size = (size_t) msize;
  97
  98         return 0;
  99
 100 out_err:
 101         errno = EINVAL;
 102         return -1;
 103 }
 104
 105 /**
 106  * Read blob's contents into memory.
 107  *
 108  * \param sha1 blob's SHA1
 109  * \param buf pointer to return the blob's contents (should be freed
 110  *            with free(), might be NULL)
 111  * \param size pointer to return the blob's size (might be NULL)
 112  *
 113  * \returns 0 on success, -1 otherwise
 114  */
 115 int git_repo_blob_read(unsigned char *sha1, void **buf, size_t *size)
 116 {
 117         return repo_read_object(sha1, OBJ_BLOB, buf, size);
 118 }
 119
 120 /**
 121  * Read commit's contents into memory.
 122  *
 123  * \param sha1 commit's SHA1
 124  * \param buf pointer to return the commit's contents (should be
 125  *            freed with free(), might be NULL)
 126  * \param size pointer to return the commit's size (might be NULL)
 127  *
 128  * \returns 0 on success, -1 otherwise
 129  */
 130 int git_repo_commit_read(unsigned char *sha1, void **buf, size_t *size)
 131 {
 132         return repo_read_object(sha1, OBJ_COMMIT, buf, size);
 133 }
 134
 135 /**
 136  * Read tree's contents into memory.
 137  *
 138  * \param sha1 tree's SHA1
 139  * \param buf pointer to return the tree's contents (should be
 140  *            freed with free(), might be NULL)
 141  * \param size pointer to return the tree's size (might be NULL)
 142  *
 143  * \returns 0 on success, -1 otherwise
 144  */
 145 int git_repo_tree_read(unsigned char *sha1, void **buf, size_t *size)
 146 {
 147         return repo_read_object(sha1, OBJ_TREE, buf, size);
 148 }
 149
 150 /**
 151  * Read tag's contents into memory.
 152  *
 153  * \param sha1 tag's SHA1
 154  * \param buf pointer to return the tag's contents into (should be
 155  *            freed with free(), might be NULL)
 156  * \param size pointer to return the tag's size (might be NULL)
 157  *
 158  * \returns 0 on success, -1 otherwise
 159  */
 160 int git_repo_tag_read(unsigned char *sha1, void **buf, size_t *size)
 161 {
 162         return repo_read_object(sha1, OBJ_TAG, buf, size);
 163 }