cleanup: move error handling into read_retry

If read_retry fails to read the expected amount of data (EOF or otherwise),
it is almost always an error.

This commit renames read_retry to read_data and moves error handling
into the function, making a lot of error handling code redundant.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

3 files changed, 10 insertions, 45 deletions

diff --git a/lib/tar/read_header.c b/lib/tar/read_header.c
index 94c4a69..1769e0a 100644
--- a/lib/tar/read_header.c
+++ b/lib/tar/read_header.c
@@ -31,18 +31,12 @@ static int check_version(const tar_header_t *hdr)
 static char *record_to_memory(int fd, uint64_t size)
 {
 	char *buffer = malloc(size + 1);
-	ssize_t ret;
 
 	if (buffer == NULL)
 		goto fail_errno;
 
-	ret = read_retry(fd, buffer, size);
-	if (ret == 0)
-		goto fail_eof;
-	if (ret < 0)
-		goto fail_errno;
-	if ((uint64_t)ret < size)
-		goto fail_eof;
+	if (read_data("reading tar record", fd, buffer, size))
+		goto fail;
 
 	if (skip_padding(fd, size))
 		goto fail;
@@ -52,9 +46,6 @@ static char *record_to_memory(int fd, uint64_t size)
 fail_errno:
 	perror("reading tar record");
 	goto fail;
-fail_eof:
-	fputs("reading tar record: unexpected end of file\n", stderr);
-	goto fail;
 fail:
 	free(buffer);
 	return NULL;
@@ -416,18 +407,13 @@ int read_header(int fd, tar_header_decoded_t *out)
 	bool prev_was_zero = false;
 	uint64_t pax_size;
 	tar_header_t hdr;
-	int ret, version;
+	int version;
 
 	memset(out, 0, sizeof(*out));
 
 	for (;;) {
-		ret = read_retry(fd, &hdr, sizeof(hdr));
-		if (ret == 0)
-			goto out_eof;
-		if (ret < 0)
-			goto fail_errno;
-		if (ret < (int)sizeof(hdr))
-			goto fail_eof;
+		if (read_data("reading tar header", fd, &hdr, sizeof(hdr)))
+			goto fail;
 
 		if (is_zero_block(&hdr)) {
 			if (prev_was_zero)
@@ -499,12 +485,6 @@ int read_header(int fd, tar_header_decoded_t *out)
 out_eof:
 	clear_header(out);
 	return 1;
-fail_errno:
-	perror("reading tar header");
-	goto fail;
-fail_eof:
-	fputs("reading tar header: unexpected end of file\n", stderr);
-	goto fail;
 fail_magic:
 	fputs("input is not a ustar tar archive!\n", stderr);
 	goto fail;
diff --git a/lib/tar/read_sparse_map_old.c b/lib/tar/read_sparse_map_old.c
index c0b2d0d..41d309a 100644
--- a/lib/tar/read_sparse_map_old.c
+++ b/lib/tar/read_sparse_map_old.c
@@ -6,7 +6,6 @@ sparse_map_t *read_gnu_old_sparse(int fd, tar_header_t *hdr)
 	sparse_map_t *list = NULL, *end = NULL, *node;
 	gnu_sparse_t sph;
 	uint64_t off, sz;
-	ssize_t ret;
 	int i;
 
 	for (i = 0; i < 4; ++i) {
@@ -41,11 +40,10 @@ sparse_map_t *read_gnu_old_sparse(int fd, tar_header_t *hdr)
 		return list;
 
 	do {
-		ret = read_retry(fd, &sph, sizeof(sph));
-		if (ret < 0)
-			goto fail_errno;
-		if ((size_t)ret < sizeof(sph))
-			goto fail_eof;
+		if (read_data("reading GNU sparse header",
+			      fd, &sph, sizeof(sph))) {
+			goto fail;
+		}
 
 		for (i = 0; i < 21; ++i) {
 			if (!isdigit(sph.sparse[i].offset[0]))
@@ -77,9 +75,6 @@ sparse_map_t *read_gnu_old_sparse(int fd, tar_header_t *hdr)
 	} while (sph.isextended != 0);
 
 	return list;
-fail_eof:
-	fputs("parsing GNU sparse header: unexpected end of file", stderr);
-	goto fail;
 fail_errno:
 	perror("parsing GNU sparse header");
 	goto fail;
diff --git a/lib/tar/skip.c b/lib/tar/skip.c
index 69208b2..28c02be 100644
--- a/lib/tar/skip.c
+++ b/lib/tar/skip.c
@@ -7,7 +7,6 @@
 static int skip_bytes(int fd, uint64_t size)
 {
 	unsigned char buffer[1024];
-	ssize_t ret;
 	size_t diff;
 
 	while (size != 0) {
@@ -15,17 +14,8 @@ static int skip_bytes(int fd, uint64_t size)
 		if (diff > size)
 			diff = size;
 
-		ret = read_retry(fd, buffer, diff);
-
-		if (ret < 0) {
-			perror("reading tar record data");
-			return -1;
-		}
-
-		if ((size_t)ret < diff) {
-			fputs("unexpected end of file\n", stderr);
+		if (read_data("reading tar record padding", fd, buffer, diff))
 			return -1;
-		}
 
 		size -= diff;
 	}