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authorJunio C Hamano <gitster@pobox.com>2023-03-17 14:03:08 -0700
committerJunio C Hamano <gitster@pobox.com>2023-03-17 14:03:09 -0700
commit88cc8ed8bc7d4bc9521b426e95ae2a38d3aec13a (patch)
tree856c32df7cde0ad5322804cddddc5ab09d3128e6 /hex.h
parentf17d232f14135c9cce6e043389a9b7c434443606 (diff)
parentf524970185963a180ecf3a750a31405c4d0de484 (diff)
downloadgit-88cc8ed8bc7d4bc9521b426e95ae2a38d3aec13a.tar.xz
Merge branch 'en/header-cleanup'
Code clean-up to clarify the rule that "git-compat-util.h" must be the first to be included. * en/header-cleanup: diff.h: remove unnecessary include of object.h Remove unnecessary includes of builtin.h treewide: replace cache.h with more direct headers, where possible replace-object.h: move read_replace_refs declaration from cache.h to here object-store.h: move struct object_info from cache.h dir.h: refactor to no longer need to include cache.h object.h: stop depending on cache.h; make cache.h depend on object.h ident.h: move ident-related declarations out of cache.h pretty.h: move has_non_ascii() declaration from commit.h cache.h: remove dependence on hex.h; make other files include it explicitly hex.h: move some hex-related declarations from cache.h hash.h: move some oid-related declarations from cache.h alloc.h: move ALLOC_GROW() functions from cache.h treewide: remove unnecessary cache.h includes in source files treewide: remove unnecessary cache.h includes treewide: remove unnecessary git-compat-util.h includes in headers treewide: ensure one of the appropriate headers is sourced first
Diffstat (limited to 'hex.h')
-rw-r--r--hex.h84
1 files changed, 84 insertions, 0 deletions
diff --git a/hex.h b/hex.h
new file mode 100644
index 0000000000..e2abfc56fa
--- /dev/null
+++ b/hex.h
@@ -0,0 +1,84 @@
+#ifndef HEX_H
+#define HEX_H
+
+#include "hash.h"
+
+extern const signed char hexval_table[256];
+static inline unsigned int hexval(unsigned char c)
+{
+ return hexval_table[c];
+}
+
+/*
+ * Convert two consecutive hexadecimal digits into a char. Return a
+ * negative value on error. Don't run over the end of short strings.
+ */
+static inline int hex2chr(const char *s)
+{
+ unsigned int val = hexval(s[0]);
+ return (val & ~0xf) ? val : (val << 4) | hexval(s[1]);
+}
+
+/*
+ * Try to read a SHA1 in hexadecimal format from the 40 characters
+ * starting at hex. Write the 20-byte result to sha1 in binary form.
+ * Return 0 on success. Reading stops if a NUL is encountered in the
+ * input, so it is safe to pass this function an arbitrary
+ * null-terminated string.
+ */
+int get_sha1_hex(const char *hex, unsigned char *sha1);
+int get_oid_hex(const char *hex, struct object_id *sha1);
+
+/* Like get_oid_hex, but for an arbitrary hash algorithm. */
+int get_oid_hex_algop(const char *hex, struct object_id *oid, const struct git_hash_algo *algop);
+
+/*
+ * Read `len` pairs of hexadecimal digits from `hex` and write the
+ * values to `binary` as `len` bytes. Return 0 on success, or -1 if
+ * the input does not consist of hex digits).
+ */
+int hex_to_bytes(unsigned char *binary, const char *hex, size_t len);
+
+/*
+ * Convert a binary hash in "unsigned char []" or an object name in
+ * "struct object_id *" to its hex equivalent. The `_r` variant is reentrant,
+ * and writes the NUL-terminated output to the buffer `out`, which must be at
+ * least `GIT_MAX_HEXSZ + 1` bytes, and returns a pointer to out for
+ * convenience.
+ *
+ * The non-`_r` variant returns a static buffer, but uses a ring of 4
+ * buffers, making it safe to make multiple calls for a single statement, like:
+ *
+ * printf("%s -> %s", hash_to_hex(one), hash_to_hex(two));
+ * printf("%s -> %s", oid_to_hex(one), oid_to_hex(two));
+ */
+char *hash_to_hex_algop_r(char *buffer, const unsigned char *hash, const struct git_hash_algo *);
+char *oid_to_hex_r(char *out, const struct object_id *oid);
+char *hash_to_hex_algop(const unsigned char *hash, const struct git_hash_algo *); /* static buffer result! */
+char *hash_to_hex(const unsigned char *hash); /* same static buffer */
+char *oid_to_hex(const struct object_id *oid); /* same static buffer */
+
+/*
+ * Parse a 40-character hexadecimal object ID starting from hex, updating the
+ * pointer specified by end when parsing stops. The resulting object ID is
+ * stored in oid. Returns 0 on success. Parsing will stop on the first NUL or
+ * other invalid character. end is only updated on success; otherwise, it is
+ * unmodified.
+ */
+int parse_oid_hex(const char *hex, struct object_id *oid, const char **end);
+
+/* Like parse_oid_hex, but for an arbitrary hash algorithm. */
+int parse_oid_hex_algop(const char *hex, struct object_id *oid, const char **end,
+ const struct git_hash_algo *algo);
+
+
+/*
+ * These functions work like get_oid_hex and parse_oid_hex, but they will parse
+ * a hex value for any algorithm. The algorithm is detected based on the length
+ * and the algorithm in use is returned. If this is not a hex object ID in any
+ * algorithm, returns GIT_HASH_UNKNOWN.
+ */
+int get_oid_hex_any(const char *hex, struct object_id *oid);
+int parse_oid_hex_any(const char *hex, struct object_id *oid, const char **end);
+
+#endif