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>

6 files changed, 25 insertions, 100 deletions

diff --git a/lib/sqfs/data_reader.c b/lib/sqfs/data_reader.c
index 7f857b2..96ccb39 100644
--- a/lib/sqfs/data_reader.c
+++ b/lib/sqfs/data_reader.c
@@ -110,13 +110,9 @@ int data_reader_dump_file(data_reader_t *data, file_info_t *fi, int outfd,
 			if (bs == 0) {
 				memset(data->buffer, 0, unpackedsz);
 				compressed = false;
-			} else {
-				ret = read_retry(data->sqfsfd, data->buffer, bs);
-				if (ret < 0)
-					goto fail_rd;
-
-				if ((size_t)ret < bs)
-					goto fail_trunc;
+			} else if (read_data("reading data block",
+					     data->sqfsfd, data->buffer, bs)) {
+				return -1;
 			}
 
 			if (compressed) {
@@ -163,12 +159,6 @@ fail_sparse:
 fail_seek:
 	perror("seek on squashfs");
 	return -1;
-fail_rd:
-	perror("reading from squashfs");
-	return -1;
-fail_trunc:
-	fputs("reading from squashfs: unexpected end of file\n", stderr);
-	return -1;
 fail_bs:
 	fputs("found compressed block larger than block size\n", stderr);
 	return -1;
diff --git a/lib/sqfs/data_writer.c b/lib/sqfs/data_writer.c
index eebd2a4..64e27fa 100644
--- a/lib/sqfs/data_writer.c
+++ b/lib/sqfs/data_writer.c
@@ -160,7 +160,6 @@ int write_data_from_fd(data_writer_t *data, file_info_t *fi,
 		       int infd, int flags)
 {
 	uint64_t count;
-	ssize_t ret;
 	size_t diff;
 
 	if ((flags & DW_ALLIGN_DEVBLK) && allign_file(data) != 0)
@@ -174,11 +173,8 @@ int write_data_from_fd(data_writer_t *data, file_info_t *fi,
 		diff = count > (uint64_t)data->super->block_size ?
 			data->super->block_size : count;
 
-		ret = read_retry(infd, data->block, diff);
-		if (ret < 0)
-			goto fail_read;
-		if ((size_t)ret < diff)
-			goto fail_trunc;
+		if (read_data(fi->input_file, infd, data->block, diff))
+			return -1;
 
 		if (flush_data_block(data, diff, fi, flags))
 			return -1;
@@ -188,12 +184,6 @@ int write_data_from_fd(data_writer_t *data, file_info_t *fi,
 		return -1;
 
 	return 0;
-fail_read:
-	perror(fi->input_file);
-	return -1;
-fail_trunc:
-	fprintf(stderr, "%s: truncated read\n", fi->input_file);
-	return -1;
 }
 
 int write_data_from_fd_condensed(data_writer_t *data, file_info_t *fi,
@@ -202,7 +192,6 @@ int write_data_from_fd_condensed(data_writer_t *data, file_info_t *fi,
 	size_t start, count, diff;
 	sparse_map_t *m;
 	uint64_t offset;
-	ssize_t ret;
 
 	if ((flags & DW_ALLIGN_DEVBLK) && allign_file(data) != 0)
 		return -1;
@@ -246,12 +235,10 @@ int write_data_from_fd_condensed(data_writer_t *data, file_info_t *fi,
 			if (start + count > diff)
 				count = diff - start;
 
-			ret = read_retry(infd, (char *)data->block + start,
-					 count);
-			if (ret < 0)
-				goto fail_read;
-			if ((size_t)ret < count)
-				goto fail_trunc;
+			if (read_data(fi->input_file, infd,
+				      (char *)data->block + start, count)) {
+				return -1;
+			}
 
 			map = map->next;
 		}
@@ -273,12 +260,6 @@ fail_map:
 		"%s: sparse file map is unordered or self overlapping\n",
 		fi->input_file);
 	return -1;
-fail_read:
-	perror(fi->input_file);
-	return -1;
-fail_trunc:
-	fprintf(stderr, "%s: truncated read\n", fi->input_file);
-	return -1;
 }
 
 data_writer_t *data_writer_create(sqfs_super_t *super, compressor_t *cmp,
diff --git a/lib/sqfs/frag_reader.c b/lib/sqfs/frag_reader.c
index 0d13bcd..6fa160b 100644
--- a/lib/sqfs/frag_reader.c
+++ b/lib/sqfs/frag_reader.c
@@ -42,16 +42,8 @@ static int precache_block(frag_reader_t *f, size_t i)
 		return -1;
 	}
 
-	ret = read_retry(f->fd, f->buffer, size);
-	if (ret < 0) {
-		perror("reading fragment");
+	if (read_data("reading fragment", f->fd, f->buffer, size))
 		return -1;
-	}
-
-	if ((size_t)ret < size) {
-		fputs("reading fragment: unexpected end of file\n", stderr);
-		return -1;
-	}
 
 	if (compressed) {
 		ret = f->cmp->do_block(f->cmp, f->buffer, size,
@@ -62,11 +54,12 @@ static int precache_block(frag_reader_t *f, size_t i)
 			return -1;
 		}
 
+		size = ret;
 		memmove(f->buffer, f->buffer + f->block_size, ret);
 	}
 
 	f->current_index = i;
-	f->used = ret;
+	f->used = size;
 	return 0;
 }
 
@@ -79,7 +72,6 @@ frag_reader_t *frag_reader_create(sqfs_super_t *super, int fd,
 	uint64_t *locations = NULL;
 	meta_reader_t *m = NULL;
 	frag_reader_t *f = NULL;
-	ssize_t ret;
 
 	count = super->fragment_entry_count;
 	blockcount = count / (SQFS_META_BLOCK_SIZE / sizeof(tbl[0]));
@@ -104,12 +96,10 @@ frag_reader_t *frag_reader_create(sqfs_super_t *super, int fd,
 	if (lseek(fd, super->fragment_table_start, SEEK_SET) == (off_t)-1)
 		goto fail_seek;
 
-	ret = read_retry(fd, locations, blockcount * sizeof(locations[0]));
-	if (ret < 0)
-		goto fail_rd;
-
-	if ((size_t)ret < (blockcount * sizeof(locations[0])))
-		goto fail_trunc;
+	if (read_data("reading fragment table", fd, locations,
+		      blockcount * sizeof(locations[0]))) {
+		goto fail;
+	}
 
 	for (i = 0; i < blockcount; ++i)
 		locations[i] = le64toh(locations[i]);
@@ -150,9 +140,6 @@ frag_reader_t *frag_reader_create(sqfs_super_t *super, int fd,
 fail_seek:
 	perror("seek to fragment table");
 	goto fail;
-fail_trunc:
-	fputs("reading fragment table: unexpected end of file\n", stderr);
-	goto fail;
 fail_rd:
 	perror("reading fragment table");
 	goto fail;
diff --git a/lib/sqfs/id_table_read.c b/lib/sqfs/id_table_read.c
index 58b0cf9..e13f3b1 100644
--- a/lib/sqfs/id_table_read.c
+++ b/lib/sqfs/id_table_read.c
@@ -14,7 +14,6 @@ int id_table_read(id_table_t *tbl, int fd, sqfs_super_t *super,
 	uint64_t blocks[32];
 	meta_reader_t *m;
 	uint32_t *ptr;
-	ssize_t ret;
 
 	if (tbl->ids != NULL) {
 		free(tbl->ids);
@@ -44,12 +43,10 @@ int id_table_read(id_table_t *tbl, int fd, sqfs_super_t *super,
 	if (super->id_count % 2048)
 		++block_count;
 
-	ret = read_retry(fd, blocks, sizeof(blocks[0]) * block_count);
-	if (ret < 0)
-		goto fail_rd;
-
-	if ((size_t)ret < sizeof(blocks[0]) * block_count)
-		goto fail_trunc;
+	if (read_data("reading ID table", fd, blocks,
+		      sizeof(blocks[0]) * block_count)) {
+		return -1;
+	}
 
 	for (i = 0; i < block_count; ++i)
 		blocks[i] = le64toh(blocks[i]);
@@ -83,12 +80,6 @@ int id_table_read(id_table_t *tbl, int fd, sqfs_super_t *super,
 fail_meta:
 	meta_reader_destroy(m);
 	return -1;
-fail_trunc:
-	fputs("reading ID table: unexpected end of file\n", stderr);
-	return -1;
-fail_rd:
-	perror("reading ID table");
-	return -1;
 fail_seek:
 	perror("seeking to ID table");
 	return -1;
diff --git a/lib/sqfs/meta_reader.c b/lib/sqfs/meta_reader.c
index e9b599f..c85d063 100644
--- a/lib/sqfs/meta_reader.c
+++ b/lib/sqfs/meta_reader.c
@@ -71,12 +71,8 @@ int meta_reader_seek(meta_reader_t *m, uint64_t block_start, size_t offset)
 		return -1;
 	}
 
-	ret = read_retry(m->fd, &header, 2);
-	if (ret < 0)
-		goto fail_rd;
-
-	if ((size_t)ret < 2)
-		goto fail_trunc;
+	if (read_data("reading meta data header", m->fd, &header, 2))
+		return -1;
 
 	header = le16toh(header);
 	compressed = (header & 0x8000) == 0;
@@ -94,12 +90,8 @@ int meta_reader_seek(meta_reader_t *m, uint64_t block_start, size_t offset)
 
 	memset(m->data, 0, sizeof(m->data));
 
-	ret = read_retry(m->fd, m->data, size);
-	if (ret < 0)
-		goto fail_rd;
-
-	if ((size_t)ret < size)
-		goto fail_trunc;
+	if (read_data("reading meta data block", m->fd, m->data, size))
+		return -1;
 
 	if (compressed) {
 		ret = m->cmp->do_block(m->cmp, m->data, size,
@@ -117,12 +109,6 @@ int meta_reader_seek(meta_reader_t *m, uint64_t block_start, size_t offset)
 	}
 
 	return 0;
-fail_trunc:
-	fputs("reading meta data: unexpected end of file\n", stderr);
-	return -1;
-fail_rd:
-	perror("reading meta data");
-	return -1;
 }
 
 int meta_reader_read(meta_reader_t *m, void *data, size_t size)
diff --git a/lib/sqfs/read_super.c b/lib/sqfs/read_super.c
index 7b738ea..8c43fe0 100644
--- a/lib/sqfs/read_super.c
+++ b/lib/sqfs/read_super.c
@@ -11,23 +11,13 @@ int sqfs_super_read(sqfs_super_t *super, int fd)
 {
 	size_t block_size = 0;
 	sqfs_super_t temp;
-	ssize_t ret;
 	int i;
 
 	if (lseek(fd, 0, SEEK_SET) == (off_t)-1)
 		goto fail_seek;
 
-	ret = read_retry(fd, &temp, sizeof(temp));
-
-	if (ret < 0) {
-		perror("reading super block");
+	if (read_data("reading super block", fd, &temp, sizeof(temp)))
 		return -1;
-	}
-
-	if ((size_t)ret < sizeof(temp)) {
-		fputs("reading super block: unexpected end of file\n", stderr);
-		return -1;
-	}
 
 	temp.magic = le32toh(temp.magic);
 	temp.inode_count = le32toh(temp.inode_count);