This is a trivial operation that doesn't require calling a function over and over- just do some math and indexing into a character array. Signed-off-by: Dan McGee <dan@archlinux.org> --- lib/libalpm/util.c | 24 ++++++++++++++---------- 1 files changed, 14 insertions(+), 10 deletions(-) diff --git a/lib/libalpm/util.c b/lib/libalpm/util.c index 5056b98..57869d3 100644 --- a/lib/libalpm/util.c +++ b/lib/libalpm/util.c @@ -816,6 +816,8 @@ static int sha2_file(const char *path, unsigned char output[32], int is224) } #endif +static const char *hex_digits = "0123456789abcdef"; + /** Get the md5 sum of file. * @param filename name of the file * @return the checksum on success, NULL on error @@ -829,8 +831,7 @@ char SYMEXPORT *alpm_compute_md5sum(const char *filename) ASSERT(filename != NULL, return NULL); - /* allocate 32 chars plus 1 for null */ - CALLOC(md5sum, 33, sizeof(char), return NULL); + MALLOC(md5sum, (size_t)33, return NULL); /* defined above for OpenSSL, otherwise defined in md5.h */ ret = md5_file(filename, output); @@ -841,10 +842,12 @@ char SYMEXPORT *alpm_compute_md5sum(const char *filename) /* Convert the result to something readable */ for (i = 0; i < 16; i++) { - /* sprintf is acceptable here because we know our output */ - sprintf(md5sum +(i * 2), "%02x", output[i]); + int pos = i * 2; + /* high 4 bits are first digit, low 4 are second */ + md5sum[pos] = hex_digits[output[i] >> 4]; + md5sum[pos + 1] = hex_digits[output[i] & 0x0f]; } - + md5sum[32] = '\0'; return md5sum; } @@ -861,8 +864,7 @@ char SYMEXPORT *alpm_compute_sha256sum(const char *filename) ASSERT(filename != NULL, return NULL); - /* allocate 64 chars plus 1 for null */ - CALLOC(sha256sum, 65, sizeof(char), return NULL); + MALLOC(sha256sum, (size_t)65, return NULL); /* defined above for OpenSSL, otherwise defined in sha2.h */ ret = sha2_file(filename, output, 0); @@ -873,10 +875,12 @@ char SYMEXPORT *alpm_compute_sha256sum(const char *filename) /* Convert the result to something readable */ for (i = 0; i < 32; i++) { - /* sprintf is acceptable here because we know our output */ - sprintf(sha256sum +(i * 2), "%02x", output[i]); + int pos = i * 2; + /* high 4 bits are first digit, low 4 are second */ + sha256sum[pos] = hex_digits[output[i] >> 4]; + sha256sum[pos + 1] = hex_digits[output[i] & 0x0f]; } - + sha256sum[64] = '\0'; return sha256sum; } -- 1.7.7