Merge changes from topic "sparse-file-read-enum"
* changes:
libsparse: Add "hole" mode to sparse_file_read
libsparse: Split off most of sparse_file_read_normal into a helper function
diff --git a/libsparse/img2simg.cpp b/libsparse/img2simg.cpp
index 4c2c6ca..3e24cc0 100644
--- a/libsparse/img2simg.cpp
+++ b/libsparse/img2simg.cpp
@@ -93,7 +93,7 @@
}
sparse_file_verbose(s);
- ret = sparse_file_read(s, in, false, false);
+ ret = sparse_file_read(s, in, SPARSE_READ_MODE_NORMAL, false);
if (ret) {
fprintf(stderr, "Failed to read file\n");
exit(-1);
diff --git a/libsparse/include/sparse/sparse.h b/libsparse/include/sparse/sparse.h
index 9f91269..7c52c3f 100644
--- a/libsparse/include/sparse/sparse.h
+++ b/libsparse/include/sparse/sparse.h
@@ -225,23 +225,42 @@
int (*write)(void *priv, const void *data, size_t len, unsigned int block,
unsigned int nr_blocks),
void *priv);
+
+/**
+ * enum sparse_read_mode - The method to use when reading in files
+ * @SPARSE_READ_MODE_NORMAL: The input is a regular file. Constant chunks of
+ * data (including holes) will be be converted to
+ * fill chunks.
+ * @SPARSE_READ_MODE_SPARSE: The input is an Android sparse file.
+ * @SPARSE_READ_MODE_HOLE: The input is a regular file. Holes will be converted
+ * to "don't care" chunks. Other constant chunks will
+ * be converted to fill chunks.
+ */
+enum sparse_read_mode {
+ SPARSE_READ_MODE_NORMAL = false,
+ SPARSE_READ_MODE_SPARSE = true,
+ SPARSE_READ_MODE_HOLE,
+};
+
/**
* sparse_file_read - read a file into a sparse file cookie
*
* @s - sparse file cookie
* @fd - file descriptor to read from
- * @sparse - read a file in the Android sparse file format
+ * @mode - mode to use when reading the input file
* @crc - verify the crc of a file in the Android sparse file format
*
- * Reads a file into a sparse file cookie. If sparse is true, the file is
- * assumed to be in the Android sparse file format. If sparse is false, the
- * file will be sparsed by looking for block aligned chunks of all zeros or
- * another 32 bit value. If crc is true, the crc of the sparse file will be
- * verified.
+ * Reads a file into a sparse file cookie. If @mode is
+ * %SPARSE_READ_MODE_SPARSE, the file is assumed to be in the Android sparse
+ * file format. If @mode is %SPARSE_READ_MODE_NORMAL, the file will be sparsed
+ * by looking for block aligned chunks of all zeros or another 32 bit value. If
+ * @mode is %SPARSE_READ_MODE_HOLE, the file will be sparsed like
+ * %SPARSE_READ_MODE_NORMAL, but holes in the file will be converted to "don't
+ * care" chunks. If crc is true, the crc of the sparse file will be verified.
*
* Returns 0 on success, negative errno on error.
*/
-int sparse_file_read(struct sparse_file *s, int fd, bool sparse, bool crc);
+int sparse_file_read(struct sparse_file *s, int fd, enum sparse_read_mode mode, bool crc);
/**
* sparse_file_import - import an existing sparse file
diff --git a/libsparse/sparse_read.cpp b/libsparse/sparse_read.cpp
index 0f39172..028b6be 100644
--- a/libsparse/sparse_read.cpp
+++ b/libsparse/sparse_read.cpp
@@ -457,12 +457,10 @@
return 0;
}
-static int sparse_file_read_normal(struct sparse_file* s, int fd) {
+static int do_sparse_file_read_normal(struct sparse_file* s, int fd, uint32_t* buf, int64_t offset,
+ int64_t remain) {
int ret;
- uint32_t* buf = (uint32_t*)malloc(s->block_size);
- unsigned int block = 0;
- int64_t remain = s->len;
- int64_t offset = 0;
+ unsigned int block = offset / s->block_size;
unsigned int to_read;
unsigned int i;
bool sparse_block;
@@ -476,7 +474,6 @@
ret = read_all(fd, buf, to_read);
if (ret < 0) {
error("failed to read sparse file");
- free(buf);
return ret;
}
@@ -504,20 +501,93 @@
block++;
}
- free(buf);
return 0;
}
-int sparse_file_read(struct sparse_file* s, int fd, bool sparse, bool crc) {
- if (crc && !sparse) {
+static int sparse_file_read_normal(struct sparse_file* s, int fd) {
+ int ret;
+ uint32_t* buf = (uint32_t*)malloc(s->block_size);
+
+ if (!buf)
+ return -ENOMEM;
+
+ ret = do_sparse_file_read_normal(s, fd, buf, 0, s->len);
+ free(buf);
+ return ret;
+}
+
+#ifdef __linux__
+static int sparse_file_read_hole(struct sparse_file* s, int fd) {
+ int ret;
+ uint32_t* buf = (uint32_t*)malloc(s->block_size);
+ int64_t end = 0;
+ int64_t start = 0;
+
+ if (!buf) {
+ return -ENOMEM;
+ }
+
+ do {
+ start = lseek(fd, end, SEEK_DATA);
+ if (start < 0) {
+ if (errno == ENXIO)
+ /* The rest of the file is a hole */
+ break;
+
+ error("could not seek to data");
+ free(buf);
+ return -errno;
+ } else if (start > s->len) {
+ break;
+ }
+
+ end = lseek(fd, start, SEEK_HOLE);
+ if (end < 0) {
+ error("could not seek to end");
+ free(buf);
+ return -errno;
+ }
+ end = std::min(end, s->len);
+
+ start = ALIGN_DOWN(start, s->block_size);
+ end = ALIGN(end, s->block_size);
+ if (lseek(fd, start, SEEK_SET) < 0) {
+ free(buf);
+ return -errno;
+ }
+
+ ret = do_sparse_file_read_normal(s, fd, buf, start, end - start);
+ if (ret) {
+ free(buf);
+ return ret;
+ }
+ } while (end < s->len);
+
+ free(buf);
+ return 0;
+}
+#else
+static int sparse_file_read_hole(struct sparse_file* s __unused, int fd __unused) {
+ return -ENOTSUP;
+}
+#endif
+
+int sparse_file_read(struct sparse_file* s, int fd, enum sparse_read_mode mode, bool crc) {
+ if (crc && mode != SPARSE_READ_MODE_SPARSE) {
return -EINVAL;
}
- if (sparse) {
- SparseFileFdSource source(fd);
- return sparse_file_read_sparse(s, &source, crc);
- } else {
- return sparse_file_read_normal(s, fd);
+ switch (mode) {
+ case SPARSE_READ_MODE_SPARSE: {
+ SparseFileFdSource source(fd);
+ return sparse_file_read_sparse(s, &source, crc);
+ }
+ case SPARSE_READ_MODE_NORMAL:
+ return sparse_file_read_normal(s, fd);
+ case SPARSE_READ_MODE_HOLE:
+ return sparse_file_read_hole(s, fd);
+ default:
+ return -EINVAL;
}
}