Thread: glib & g_checksum_*

Though I am a glib fan, I really cannot use the g_checksum_* functions to obtain an MD5 string that is compatible with the md5sum command.

Code:

gchar *get_hash(const gchar *filepath) {
	FILE *fp;
	if (NULL != (fp = fopen(filepath, "r+b"))) {
		guchar buffer[65536];
		gint read_bytes;
		gchar *result;
		GChecksum *checksum = g_checksum_new(hash_type);
		while ((read_bytes = fread(buffer, sizeof(buffer), 1, fp)) > 0)
			g_checksum_update(checksum, buffer, read_bytes);

		fclose(fp);
		result = (gchar *) g_checksum_get_string(checksum);
		g_checksum_free(checksum);
		return result;
	}
	return "";
}

Any idea on what is wrong with this code?
Thanks in advance for any help and or suggestion

I would say you need to make a COPY of the string returned by g_checksum_get_string(), before you call g_checksum_free()

Your fread parameters are the wrong way round.

That is, if you're wanting to return the number of bytes, as opposed to the number of buffers.

** Thank you so much!!

Code:

gchar *get_hash(const gchar *filepath, GChecksumType hash_type) {
	FILE *fp;
	if (NULL != (fp = fopen(filepath, "rb"))) {
		guchar buffer[65536];
		gint read_bytes;
		gchar *result;
		GChecksum *checksum = g_checksum_new(hash_type);
		while ((read_bytes = fread(buffer, 1, sizeof(buffer), fp)) > 0)
			g_checksum_update(checksum, buffer, read_bytes);

		result = g_strdup((gchar *) g_checksum_get_string(checksum));

		fclose(fp);
		g_checksum_free(checksum);

		return result;
	}
	return g_strdup("");
}

> guchar buffer[65536];
If you're stuck for choosing a buffer size, then the macro BUFSIZ (in stdio.h) is a good alternative.

> result = g_strdup((gchar *) g_checksum_get_string(checksum));
I can't see how this cast was necessary.