libsparse: Add sparse typed callback
Currently, sparse_file_callback uses libsparse's
own logic for reading a file into a buffer. However,
a caller may want to use their own logic for doing
this in order to customize the buffer size and parallelize
the reads/writes. Also, a caller may want to implement
fill blocks with their own logic as well. To do this
add sparse_file_typed_callback which calls a different
callback function depending on the type of the sparse
chunk being written.
Test: Use typed callback for fd writes
Bug: 78793464
Change-Id: I75955a464fc05991f806339830fdfa05fda354b9
diff --git a/libsparse/include/sparse/sparse.h b/libsparse/include/sparse/sparse.h
index 3d5fb0c..5865786 100644
--- a/libsparse/include/sparse/sparse.h
+++ b/libsparse/include/sparse/sparse.h
@@ -210,6 +210,37 @@
int (*write)(void *priv, const void *data, size_t len), void *priv);
/**
+ * sparse_file_callback_typed - call a callback for blocks based on type
+ *
+ * @s - sparse file cookie
+ * @sparse - write in the Android sparse file format
+ * @data_write - function to call for data blocks. must not be null
+ * @fd_write - function to call for fd blocks
+ * @fill_write - function to call for fill blocks
+ * @skip_write - function to call for skip blocks
+ * @priv - value that will be passed as the first argument to each write
+ *
+ * Writes a sparse file by calling callback functions. If sparse is true, the
+ * file will be written in the Android sparse file format, and fill and skip blocks
+ * along with metadata will be written with data_write. If sparse is false, the file
+ * will be expanded into normal format and fill and skip blocks will be written with
+ * the given callbacks.
+ * If a callback function is provided, the library will not unroll data into a buffer,
+ * and will instead pass it directly to the caller for custom implementation. If a
+ * callback is not provided, that type of block will be converted into a void* and
+ * written with data_write. If no callbacks other than data are provided, the behavior
+ * is the same as sparse_file_callback(). The callback should return negative on error,
+ * 0 on success.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int sparse_file_callback_typed(struct sparse_file* s, bool sparse,
+ int (*data_write)(void* priv, const void* data, size_t len),
+ int (*fd_write)(void* priv, int fd, size_t len),
+ int (*fill_write)(void* priv, uint32_t fill_val, size_t len),
+ int (*skip_write)(void* priv, int64_t len), void* priv);
+
+/**
* sparse_file_foreach_chunk - call a callback for data blocks in sparse file
*
* @s - sparse file cookie
diff --git a/libsparse/output_file.cpp b/libsparse/output_file.cpp
index fe314b3..8a21dab 100644
--- a/libsparse/output_file.cpp
+++ b/libsparse/output_file.cpp
@@ -29,6 +29,8 @@
#include <unistd.h>
#include <zlib.h>
+#include <algorithm>
+
#include "defs.h"
#include "output_file.h"
#include "sparse_crc32.h"
@@ -48,13 +50,6 @@
#define off64_t off_t
#endif
-#define min(a, b) \
- ({ \
- typeof(a) _a = (a); \
- typeof(b) _b = (b); \
- (_a < _b) ? _a : _b; \
- })
-
#define SPARSE_HEADER_MAJOR_VER 1
#define SPARSE_HEADER_MINOR_VER 0
#define SPARSE_HEADER_LEN (sizeof(sparse_header_t))
@@ -67,11 +62,14 @@
int (*skip)(struct output_file*, int64_t);
int (*pad)(struct output_file*, int64_t);
int (*write)(struct output_file*, void*, size_t);
+ int (*write_fd)(struct output_file*, int, size_t);
+ int (*write_fill)(struct output_file*, uint32_t, size_t);
void (*close)(struct output_file*);
};
struct sparse_file_ops {
int (*write_data_chunk)(struct output_file* out, unsigned int len, void* data);
+ int (*write_fd_chunk)(struct output_file* out, unsigned int len, int fd);
int (*write_fill_chunk)(struct output_file* out, unsigned int len, uint32_t fill_val);
int (*write_skip_chunk)(struct output_file* out, int64_t len);
int (*write_end_chunk)(struct output_file* out);
@@ -108,11 +106,96 @@
struct output_file_callback {
struct output_file out;
void* priv;
- int (*write)(void* priv, const void* buf, size_t len);
+ int (*data_write)(void* priv, const void* data, size_t len);
+ int (*fd_write)(void* priv, int fd, size_t len);
+ int (*fill_write)(void* priv, uint32_t fill_val, size_t len);
+ int (*skip_write)(void* priv, off64_t len);
};
#define to_output_file_callback(_o) container_of((_o), struct output_file_callback, out)
+union handle_data {
+ void* data_ptr;
+ int fd;
+};
+
+static int default_file_write_fd(struct output_file* out, int fd, size_t len) {
+ int ret;
+ int64_t aligned_offset;
+ int aligned_diff;
+ uint64_t buffer_size;
+ char* ptr;
+ int64_t offset = lseek64(fd, 0, SEEK_CUR);
+
+ if (offset < 0) {
+ return -errno;
+ }
+
+ aligned_offset = offset & ~(4096 - 1);
+ aligned_diff = offset - aligned_offset;
+ buffer_size = (uint64_t)len + (uint64_t)aligned_diff;
+
+#ifndef _WIN32
+ if (buffer_size > SIZE_MAX) {
+ return -E2BIG;
+ }
+ char* data =
+ reinterpret_cast<char*>(mmap64(NULL, buffer_size, PROT_READ, MAP_SHARED, fd, aligned_offset));
+ if (data == MAP_FAILED) {
+ return -errno;
+ }
+ ptr = data + aligned_diff;
+#else
+ char* data = reinterpret_cast<char*>(malloc(len));
+ if (!data) {
+ return -errno;
+ }
+ ret = read_all(fd, data, len);
+ if (ret < 0) {
+ free(data);
+ return -errno;
+ }
+ ptr = data;
+#endif
+
+ ret = out->ops->write(out, ptr, len);
+
+ if (out->use_crc) {
+ out->crc32 = sparse_crc32(out->crc32, ptr, len);
+ }
+
+#ifndef _WIN32
+ munmap(data, buffer_size);
+#else
+ free(data);
+#endif
+
+ return ret;
+}
+
+static int default_file_write_fill(struct output_file* out, uint32_t fill_val, size_t len) {
+ int ret;
+ unsigned int i;
+ unsigned int write_len;
+
+ /* Initialize fill_buf with the fill_val */
+ for (i = 0; i < out->block_size / sizeof(uint32_t); i++) {
+ out->fill_buf[i] = fill_val;
+ }
+
+ while (len) {
+ write_len = std::min(len, static_cast<size_t>(out->block_size));
+ ret = out->ops->write(out, out->fill_buf, write_len);
+ if (ret < 0) {
+ return ret;
+ }
+
+ len -= write_len;
+ }
+
+ return 0;
+}
+
static int file_open(struct output_file* out, int fd) {
struct output_file_normal* outn = to_output_file_normal(out);
@@ -176,6 +259,8 @@
.skip = file_skip,
.pad = file_pad,
.write = file_write,
+ .write_fd = default_file_write_fd,
+ .write_fill = default_file_write_fill,
.close = file_close,
};
@@ -231,7 +316,7 @@
struct output_file_gz* outgz = to_output_file_gz(out);
while (len > 0) {
- ret = gzwrite(outgz->gz_fd, data, min(len, (unsigned int)INT_MAX));
+ ret = gzwrite(outgz->gz_fd, data, std::min(len, static_cast<size_t>(INT_MAX)));
if (ret == 0) {
error("gzwrite %s", gzerror(outgz->gz_fd, nullptr));
return -1;
@@ -255,6 +340,8 @@
.skip = gz_file_skip,
.pad = gz_file_pad,
.write = gz_file_write,
+ .write_fd = default_file_write_fd,
+ .write_fill = default_file_write_fill,
.close = gz_file_close,
};
@@ -267,9 +354,13 @@
int to_write;
int ret;
+ if (outc->skip_write) {
+ return outc->skip_write(outc->priv, off);
+ }
+
while (off > 0) {
- to_write = min(off, (int64_t)INT_MAX);
- ret = outc->write(outc->priv, nullptr, to_write);
+ to_write = std::min(off, static_cast<int64_t>(INT_MAX));
+ ret = outc->data_write(outc->priv, nullptr, to_write);
if (ret < 0) {
return ret;
}
@@ -285,8 +376,23 @@
static int callback_file_write(struct output_file* out, void* data, size_t len) {
struct output_file_callback* outc = to_output_file_callback(out);
+ return outc->data_write(outc->priv, data, len);
+}
- return outc->write(outc->priv, data, len);
+static int callback_file_write_fd(struct output_file* out, int fd, size_t len) {
+ struct output_file_callback* outc = to_output_file_callback(out);
+ if (outc->fd_write) {
+ return outc->fd_write(outc->priv, fd, len);
+ }
+ return default_file_write_fd(out, fd, len);
+}
+
+static int callback_file_write_fill(struct output_file* out, uint32_t fill_val, size_t len) {
+ struct output_file_callback* outc = to_output_file_callback(out);
+ if (outc->fill_write) {
+ return outc->fill_write(outc->priv, fill_val, len);
+ }
+ return default_file_write_fill(out, fill_val, len);
}
static void callback_file_close(struct output_file* out) {
@@ -300,6 +406,8 @@
.skip = callback_file_skip,
.pad = callback_file_pad,
.write = callback_file_write,
+ .write_fd = callback_file_write_fd,
+ .write_fill = callback_file_write_fill,
.close = callback_file_close,
};
@@ -376,7 +484,8 @@
return 0;
}
-static int write_sparse_data_chunk(struct output_file* out, unsigned int len, void* data) {
+static int write_sparse_data_chunk_variant(struct output_file* out, unsigned int len,
+ handle_data data, bool is_fd) {
chunk_header_t chunk_header;
int rnd_up_len, zero_len;
int ret;
@@ -393,7 +502,16 @@
ret = out->ops->write(out, &chunk_header, sizeof(chunk_header));
if (ret < 0) return -1;
- ret = out->ops->write(out, data, len);
+
+ if (is_fd) {
+ // CRC is handled by write_fd
+ ret = out->ops->write_fd(out, data.fd, len);
+ } else {
+ ret = out->ops->write(out, data.data_ptr, len);
+ if (out->use_crc) {
+ out->crc32 = sparse_crc32(out->crc32, data.data_ptr, len);
+ }
+ }
if (ret < 0) return -1;
if (zero_len) {
ret = out->ops->write(out, out->zero_buf, zero_len);
@@ -401,7 +519,6 @@
}
if (out->use_crc) {
- out->crc32 = sparse_crc32(out->crc32, data, len);
if (zero_len) out->crc32 = sparse_crc32(out->crc32, out->zero_buf, zero_len);
}
@@ -411,6 +528,16 @@
return 0;
}
+static int write_sparse_data_chunk(struct output_file* out, unsigned int len, void* data_ptr) {
+ handle_data data = {data_ptr};
+ return write_sparse_data_chunk_variant(out, len, data, false /* isFd */);
+}
+
+static int write_sparse_fd_chunk(struct output_file* out, unsigned int len, int fd) {
+ handle_data data = {.fd = fd};
+ return write_sparse_data_chunk_variant(out, len, data, true /* isFd */);
+}
+
int write_sparse_end_chunk(struct output_file* out) {
chunk_header_t chunk_header;
int ret;
@@ -438,16 +565,22 @@
static struct sparse_file_ops sparse_file_ops = {
.write_data_chunk = write_sparse_data_chunk,
+ .write_fd_chunk = write_sparse_fd_chunk,
.write_fill_chunk = write_sparse_fill_chunk,
.write_skip_chunk = write_sparse_skip_chunk,
.write_end_chunk = write_sparse_end_chunk,
};
-static int write_normal_data_chunk(struct output_file* out, unsigned int len, void* data) {
+static int write_normal_data_chunk_variant(struct output_file* out, unsigned int len,
+ handle_data data, bool isFd) {
int ret;
unsigned int rnd_up_len = ALIGN(len, out->block_size);
- ret = out->ops->write(out, data, len);
+ if (isFd) {
+ ret = out->ops->write_fd(out, data.fd, len);
+ } else {
+ ret = out->ops->write(out, data.data_ptr, len);
+ }
if (ret < 0) {
return ret;
}
@@ -459,27 +592,18 @@
return ret;
}
+static int write_normal_data_chunk(struct output_file* out, unsigned int len, void* data_ptr) {
+ handle_data data = {data_ptr};
+ return write_normal_data_chunk_variant(out, len, data, false /* isFd */);
+}
+
+static int write_normal_fd_chunk(struct output_file* out, unsigned int len, int fd) {
+ handle_data data = {.fd = fd};
+ return write_normal_data_chunk_variant(out, len, data, true /* isFd */);
+}
+
static int write_normal_fill_chunk(struct output_file* out, unsigned int len, uint32_t fill_val) {
- int ret;
- unsigned int i;
- unsigned int write_len;
-
- /* Initialize fill_buf with the fill_val */
- for (i = 0; i < out->block_size / sizeof(uint32_t); i++) {
- out->fill_buf[i] = fill_val;
- }
-
- while (len) {
- write_len = min(len, out->block_size);
- ret = out->ops->write(out, out->fill_buf, write_len);
- if (ret < 0) {
- return ret;
- }
-
- len -= write_len;
- }
-
- return 0;
+ return out->ops->write_fill(out, fill_val, len);
}
static int write_normal_skip_chunk(struct output_file* out, int64_t len) {
@@ -492,6 +616,7 @@
static struct sparse_file_ops normal_file_ops = {
.write_data_chunk = write_normal_data_chunk,
+ .write_fd_chunk = write_normal_fd_chunk,
.write_fill_chunk = write_normal_fill_chunk,
.write_skip_chunk = write_normal_skip_chunk,
.write_end_chunk = write_normal_end_chunk,
@@ -589,12 +714,20 @@
return &outn->out;
}
-struct output_file* output_file_open_callback(int (*write)(void*, const void*, size_t), void* priv,
- unsigned int block_size, int64_t len, int gz __unused,
- int sparse, int chunks, int crc) {
+struct output_file* output_file_open_callback(int (*data_write)(void*, const void*, size_t),
+ int (*fd_write)(void*, int, size_t),
+ int (*fill_write)(void*, uint32_t, size_t),
+ int (*skip_write)(void*, off64_t), void* priv,
+ unsigned int block_size, int64_t len, int sparse,
+ int chunks, int crc) {
int ret;
struct output_file_callback* outc;
+ if (!data_write || (crc && (fd_write || fill_write))) {
+ errno = EINVAL;
+ return nullptr;
+ }
+
outc =
reinterpret_cast<struct output_file_callback*>(calloc(1, sizeof(struct output_file_callback)));
if (!outc) {
@@ -604,7 +737,10 @@
outc->out.ops = &callback_file_ops;
outc->priv = priv;
- outc->write = write;
+ outc->data_write = data_write;
+ outc->fd_write = fd_write;
+ outc->fill_write = fill_write;
+ outc->skip_write = skip_write;
ret = output_file_init(&outc->out, block_size, len, sparse, chunks, crc);
if (ret < 0) {
@@ -651,52 +787,8 @@
}
int write_fd_chunk(struct output_file* out, unsigned int len, int fd, int64_t offset) {
- int ret;
- int64_t aligned_offset;
- int aligned_diff;
- uint64_t buffer_size;
- char* ptr;
-
- aligned_offset = offset & ~(4096 - 1);
- aligned_diff = offset - aligned_offset;
- buffer_size = (uint64_t)len + (uint64_t)aligned_diff;
-
-#ifndef _WIN32
- if (buffer_size > SIZE_MAX) return -E2BIG;
- char* data =
- reinterpret_cast<char*>(mmap64(nullptr, buffer_size, PROT_READ, MAP_SHARED, fd, aligned_offset));
- if (data == MAP_FAILED) {
- return -errno;
- }
- ptr = data + aligned_diff;
-#else
- off64_t pos;
- char* data = reinterpret_cast<char*>(malloc(len));
- if (!data) {
- return -errno;
- }
- pos = lseek64(fd, offset, SEEK_SET);
- if (pos < 0) {
- free(data);
- return -errno;
- }
- ret = read_all(fd, data, len);
- if (ret < 0) {
- free(data);
- return ret;
- }
- ptr = data;
-#endif
-
- ret = out->sparse_ops->write_data_chunk(out, len, ptr);
-
-#ifndef _WIN32
- munmap(data, buffer_size);
-#else
- free(data);
-#endif
-
- return ret;
+ lseek64(fd, offset, SEEK_SET);
+ return out->sparse_ops->write_fd_chunk(out, len, fd);
}
/* Write a contiguous region of data blocks from a file */
diff --git a/libsparse/output_file.h b/libsparse/output_file.h
index 278430b..114582e 100644
--- a/libsparse/output_file.h
+++ b/libsparse/output_file.h
@@ -22,14 +22,18 @@
#endif
#include <sparse/sparse.h>
+#include <sys/types.h>
struct output_file;
struct output_file* output_file_open_fd(int fd, unsigned int block_size, int64_t len, int gz,
int sparse, int chunks, int crc);
-struct output_file* output_file_open_callback(int (*write)(void*, const void*, size_t), void* priv,
- unsigned int block_size, int64_t len, int gz,
- int sparse, int chunks, int crc);
+struct output_file* output_file_open_callback(int (*data_write)(void*, const void*, size_t),
+ int (*fd_write)(void*, int, size_t),
+ int (*fill_write)(void*, uint32_t, size_t),
+ int (*skip_write)(void*, off64_t), void* priv,
+ unsigned int block_size, int64_t len, int sparse,
+ int chunks, int crc);
int write_data_chunk(struct output_file* out, unsigned int len, void* data);
int write_fill_chunk(struct output_file* out, unsigned int len, uint32_t fill_val);
int write_file_chunk(struct output_file* out, unsigned int len, const char* file, int64_t offset);
diff --git a/libsparse/sparse.cpp b/libsparse/sparse.cpp
index cb288c5..f5ca907 100644
--- a/libsparse/sparse.cpp
+++ b/libsparse/sparse.cpp
@@ -160,7 +160,30 @@
struct output_file* out;
chunks = sparse_count_chunks(s);
- out = output_file_open_callback(write, priv, s->block_size, s->len, false, sparse, chunks, crc);
+ out = output_file_open_callback(write, nullptr, nullptr, nullptr, priv, s->block_size, s->len,
+ sparse, chunks, crc);
+
+ if (!out) return -ENOMEM;
+
+ ret = write_all_blocks(s, out);
+
+ output_file_close(out);
+
+ return ret;
+}
+
+int sparse_file_callback_typed(struct sparse_file* s, bool sparse,
+ int (*data_write)(void* priv, const void* data, size_t len),
+ int (*fd_write)(void* priv, int fd, size_t len),
+ int (*fill_write)(void* priv, uint32_t fill_val, size_t len),
+ int (*skip_write)(void* priv, int64_t len), void* priv) {
+ int ret;
+ int chunks;
+ struct output_file* out;
+
+ chunks = sparse_count_chunks(s);
+ out = output_file_open_callback(data_write, fd_write, fill_write, skip_write, priv, s->block_size,
+ s->len, sparse, chunks, false);
if (!out) return -ENOMEM;
@@ -198,8 +221,8 @@
chk.write = write;
chk.block = chk.nr_blocks = 0;
chunks = sparse_count_chunks(s);
- out = output_file_open_callback(foreach_chunk_write, &chk, s->block_size, s->len, false, sparse,
- chunks, crc);
+ out = output_file_open_callback(foreach_chunk_write, nullptr, nullptr, nullptr, &chk,
+ s->block_size, s->len, sparse, chunks, crc);
if (!out) return -ENOMEM;
@@ -227,8 +250,8 @@
int64_t count = 0;
struct output_file* out;
- out = output_file_open_callback(out_counter_write, &count, s->block_size, s->len, false, sparse,
- chunks, crc);
+ out = output_file_open_callback(out_counter_write, nullptr, nullptr, nullptr, &count,
+ s->block_size, s->len, sparse, chunks, crc);
if (!out) {
return -1;
}
@@ -267,8 +290,8 @@
len -= overhead;
start = backed_block_iter_new(from->backed_block_list);
- out_counter = output_file_open_callback(out_counter_write, &count, to->block_size, to->len, false,
- true, 0, false);
+ out_counter = output_file_open_callback(out_counter_write, nullptr, nullptr, nullptr, &count,
+ to->block_size, to->len, true, 0, false);
if (!out_counter) {
return nullptr;
}