hex.h

   1 #ifndef HEX_H
   2 #define HEX_H
   3
   4 #include "hash-ll.h"
   5 #include "hex-ll.h"
   6
   7 /*
   8  * Try to read a hash (specified by the_hash_algo) in hexadecimal
   9  * format from the 40 (or whatever length the hash algorithm uses)
  10  * characters starting at hex.  Write the 20-byte (or the length of
  11  * the hash) result to hash in binary form.
  12  * Return 0 on success.  Reading stops if a NUL is encountered in the
  13  * input, so it is safe to pass this function an arbitrary
  14  * null-terminated string.
  15  */
  16 int get_hash_hex(const char *hex, unsigned char *hash);
  17 int get_oid_hex(const char *hex, struct object_id *oid);
  18
  19 /* Like get_oid_hex, but for an arbitrary hash algorithm. */
  20 int get_oid_hex_algop(const char *hex, struct object_id *oid, const struct git_hash_algo *algop);
  21
  22 /*
  23  * Convert a binary hash in "unsigned char []" or an object name in
  24  * "struct object_id *" to its hex equivalent. The `_r` variant is reentrant,
  25  * and writes the NUL-terminated output to the buffer `out`, which must be at
  26  * least `GIT_MAX_HEXSZ + 1` bytes, and returns a pointer to out for
  27  * convenience.
  28  *
  29  * The non-`_r` variant returns a static buffer, but uses a ring of 4
  30  * buffers, making it safe to make multiple calls for a single statement, like:
  31  *
  32  *   printf("%s -> %s", hash_to_hex(one), hash_to_hex(two));
  33  *   printf("%s -> %s", oid_to_hex(one), oid_to_hex(two));
  34  */
  35 char *hash_to_hex_algop_r(char *buffer, const unsigned char *hash, const struct git_hash_algo *);
  36 char *oid_to_hex_r(char *out, const struct object_id *oid);
  37 char *hash_to_hex_algop(const unsigned char *hash, const struct git_hash_algo *);       /* static buffer result! */
  38 char *hash_to_hex(const unsigned char *hash);                                           /* same static buffer */
  39 char *oid_to_hex(const struct object_id *oid);                                          /* same static buffer */
  40
  41 /*
  42  * Parse a 40-character hexadecimal object ID starting from hex, updating the
  43  * pointer specified by end when parsing stops.  The resulting object ID is
  44  * stored in oid.  Returns 0 on success.  Parsing will stop on the first NUL or
  45  * other invalid character.  end is only updated on success; otherwise, it is
  46  * unmodified.
  47  */
  48 int parse_oid_hex(const char *hex, struct object_id *oid, const char **end);
  49
  50 /* Like parse_oid_hex, but for an arbitrary hash algorithm. */
  51 int parse_oid_hex_algop(const char *hex, struct object_id *oid, const char **end,
  52                         const struct git_hash_algo *algo);
  53
  54
  55 /*
  56  * These functions work like get_oid_hex and parse_oid_hex, but they will parse
  57  * a hex value for any algorithm. The algorithm is detected based on the length
  58  * and the algorithm in use is returned. If this is not a hex object ID in any
  59  * algorithm, returns GIT_HASH_UNKNOWN.
  60  */
  61 int get_oid_hex_any(const char *hex, struct object_id *oid);
  62 int parse_oid_hex_any(const char *hex, struct object_id *oid, const char **end);
  63
  64 #endif