[pacman-dev] [PATCH] Created hex_representation() in lib/libalpm/util.c which is used in alpm_compute_md5sum() and alpm_compute_sha256sum().
[PATCH] Created hex_representation() in lib/libalpm/util.c which is used in alpm_compute_md5sum() and alpm_compute_sha256sum(). Signed-off-by: Diogo Sousa <diogogsousa@gmail.com> --- lib/libalpm/util.c | 56 ++++++++++++++++++++++++++-------------------------- 1 files changed, 28 insertions(+), 28 deletions(-) diff --git a/lib/libalpm/util.c b/lib/libalpm/util.c index 4eeb0cd..399331a 100644 --- a/lib/libalpm/util.c +++ b/lib/libalpm/util.c @@ -917,7 +917,30 @@ static int sha2_file(const char *path, unsigned char output[32], int is224) } #endif -static const char *hex_digits = "0123456789abcdef"; +/** Create a string representing bytes in hexadecimal. + * + * @param bytes the bytes to represent in hexadecimal. + * @param size number of bytes to consider. + * @return a nul terminated string with the hexadecimal representation + * of bytes or NULL on error. This string must be freed. + */ +static char *hex_representation(unsigned char *bytes, size_t size) +{ + static const char *hex_digits = "0123456789abcdef"; + char *str; + int i; + + MALLOC(str, 2 * size + 1, return NULL); + + for (i = 0; i < size; i++) { + str[2 * i] = hex_digits[bytes[i] >> 4]; + str[2 * i + 1] = hex_digits[bytes[i] & 0x0f]; + } + + str[2 * size] = '\0'; + + return str; +} /** Get the md5 sum of file. * @param filename name of the file @@ -927,29 +950,17 @@ static const char *hex_digits = "0123456789abcdef"; char SYMEXPORT *alpm_compute_md5sum(const char *filename) { unsigned char output[16]; - char *md5sum; - int ret, i; + int ret; ASSERT(filename != NULL, return NULL); - MALLOC(md5sum, (size_t)33, return NULL); - /* defined above for OpenSSL, otherwise defined in md5.h */ ret = md5_file(filename, output); if(ret > 0) { - free(md5sum); return NULL; } - /* Convert the result to something readable */ - for(i = 0; i < 16; 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; + return hex_representation(output, 16); } /** Get the sha256 sum of file. @@ -960,29 +971,18 @@ char SYMEXPORT *alpm_compute_md5sum(const char *filename) char SYMEXPORT *alpm_compute_sha256sum(const char *filename) { unsigned char output[32]; - char *sha256sum; - int ret, i; + int ret; ASSERT(filename != NULL, return NULL); - MALLOC(sha256sum, (size_t)65, return NULL); /* defined above for OpenSSL, otherwise defined in sha2.h */ ret = sha2_file(filename, output, 0); if(ret > 0) { - free(sha256sum); return NULL; } - /* Convert the result to something readable */ - for(i = 0; i < 32; 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; + return hex_representation(output, 32); } /** Calculates a file's MD5 or SHA2 digest and compares it to an expected value. -- 1.7.8
participants (1)
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Diogo Sousa