Migrate file istream/ostream from libio to libsquashfs

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

5 files changed, 750 insertions, 2 deletions

diff --git a/lib/sqfs/Makemodule.am b/lib/sqfs/Makemodule.am
index 2727b11..83ca478 100644
--- a/lib/sqfs/Makemodule.am
+++ b/lib/sqfs/Makemodule.am
@@ -57,12 +57,15 @@ libsquashfs_la_SOURCES += lib/util/src/mempool.c include/util/mempool.h
 endif
 
 if WINDOWS
-libsquashfs_la_SOURCES += lib/sqfs/src/win32/io_file.c
+libsquashfs_la_SOURCES += lib/sqfs/src/win32/io_file.c \
+		lib/sqfs/src/win32/ostream.c lib/sqfs/src/win32/istream.c
+
 libsquashfs_la_CFLAGS += -DWINVER=0x0600 -D_WIN32_WINNT=0x0600
 libsquashfs_la_CFLAGS += -Wc,-static-libgcc
 libsquashfs_la_LDFLAGS += -no-undefined -avoid-version
 else
-libsquashfs_la_SOURCES += lib/sqfs/src/unix/io_file.c
+libsquashfs_la_SOURCES += lib/sqfs/src/unix/io_file.c \
+		lib/sqfs/src/unix/ostream.c lib/sqfs/src/unix/istream.c
 endif
 
 if HAVE_PTHREAD
diff --git a/lib/sqfs/src/unix/istream.c b/lib/sqfs/src/unix/istream.c
new file mode 100644
index 0000000..fd2f120
--- /dev/null
+++ b/lib/sqfs/src/unix/istream.c
@@ -0,0 +1,169 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * istream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "config.h"
+
+#include "sqfs/io.h"
+#include "sqfs/error.h"
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+
+#define BUFSZ (131072)
+
+typedef struct {
+	sqfs_istream_t base;
+	char *path;
+	int fd;
+
+	bool eof;
+	size_t buffer_offset;
+	size_t buffer_used;
+	sqfs_u8 buffer[BUFSZ];
+} file_istream_t;
+
+static int precache(sqfs_istream_t *strm)
+{
+	file_istream_t *file = (file_istream_t *)strm;
+
+	if (file->eof)
+		return 0;
+
+	if (file->buffer_offset > 0 &&
+	    file->buffer_offset < file->buffer_used) {
+		memmove(file->buffer, file->buffer + file->buffer_offset,
+			file->buffer_used - file->buffer_offset);
+	}
+
+	file->buffer_used -= file->buffer_offset;
+	file->buffer_offset = 0;
+
+	while (file->buffer_used < BUFSZ) {
+		ssize_t ret = read(file->fd, file->buffer + file->buffer_used,
+				   BUFSZ - file->buffer_used);
+
+		if (ret == 0) {
+			file->eof = true;
+			break;
+		}
+
+		if (ret < 0) {
+			if (errno == EINTR)
+				continue;
+			return SQFS_ERROR_IO;
+		}
+
+		file->buffer_used += ret;
+	}
+
+	return 0;
+}
+
+static int file_get_buffered_data(sqfs_istream_t *strm, const sqfs_u8 **out,
+				  size_t *size, size_t want)
+{
+	file_istream_t *file = (file_istream_t *)strm;
+
+	if (want > BUFSZ)
+		want = BUFSZ;
+
+	if (file->buffer_used == 0 ||
+	    (file->buffer_used - file->buffer_offset) < want) {
+		int ret = precache(strm);
+		if (ret)
+			return ret;
+	}
+
+	*out = file->buffer + file->buffer_offset;
+	*size = file->buffer_used - file->buffer_offset;
+	return (file->eof && *size == 0) ? 1 : 0;
+}
+
+static void file_advance_buffer(sqfs_istream_t *strm, size_t count)
+{
+	file_istream_t *file = (file_istream_t *)strm;
+
+	assert(count <= file->buffer_used);
+
+	file->buffer_offset += count;
+
+	assert(file->buffer_offset <= file->buffer_used);
+}
+
+static const char *file_get_filename(sqfs_istream_t *strm)
+{
+	return ((file_istream_t *)strm)->path;
+}
+
+static void file_destroy(sqfs_object_t *obj)
+{
+	file_istream_t *file = (file_istream_t *)obj;
+
+	close(file->fd);
+	free(file->path);
+	free(file);
+}
+
+int sqfs_istream_open_handle(sqfs_istream_t **out, const char *path,
+			     sqfs_file_handle_t fd)
+{
+	file_istream_t *file = calloc(1, sizeof(*file));
+	sqfs_istream_t *strm = (sqfs_istream_t *)file;
+
+	if (file == NULL)
+		return SQFS_ERROR_ALLOC;
+
+	sqfs_object_init(file, file_destroy, NULL);
+
+	file->path = strdup(path);
+	if (file->path == NULL) {
+		int temp = errno;
+		free(file);
+		errno = temp;
+		return SQFS_ERROR_ALLOC;
+	}
+
+	file->fd = dup(fd);
+	if (file->fd < 0) {
+		int temp = errno;
+		free(file->path);
+		free(file);
+		errno = temp;
+		return SQFS_ERROR_IO;
+	}
+	close(fd);
+
+	strm->get_buffered_data = file_get_buffered_data;
+	strm->advance_buffer = file_advance_buffer;
+	strm->get_filename = file_get_filename;
+
+	*out = strm;
+	return 0;
+}
+
+int sqfs_istream_open_file(sqfs_istream_t **out, const char *path)
+{
+	sqfs_file_handle_t fd;
+	int ret;
+
+	ret = sqfs_open_native_file(&fd, path, SQFS_FILE_OPEN_READ_ONLY);
+	if (ret)
+		return ret;
+
+	ret = sqfs_istream_open_handle(out, path, fd);
+	if (ret != 0) {
+		int temp = errno;
+		close(fd);
+		errno = temp;
+	}
+
+	return ret;
+}
diff --git a/lib/sqfs/src/unix/ostream.c b/lib/sqfs/src/unix/ostream.c
new file mode 100644
index 0000000..89982c1
--- /dev/null
+++ b/lib/sqfs/src/unix/ostream.c
@@ -0,0 +1,205 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * ostream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "config.h"
+
+#include "sqfs/io.h"
+#include "sqfs/error.h"
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+
+typedef struct {
+	sqfs_ostream_t base;
+	char *path;
+	int flags;
+	int fd;
+
+	off_t sparse_count;
+	off_t size;
+} file_ostream_t;
+
+static int write_all(file_ostream_t *file, const sqfs_u8 *data, size_t size)
+{
+	while (size > 0) {
+		ssize_t ret = write(file->fd, data, size);
+
+		if (ret == 0) {
+			errno = EPIPE;
+			return SQFS_ERROR_IO;
+		}
+
+		if (ret < 0) {
+			if (errno == EINTR)
+				continue;
+			return SQFS_ERROR_IO;
+		}
+
+		file->size += ret;
+		size -= ret;
+		data += ret;
+	}
+
+	return 0;
+}
+
+static int realize_sparse(file_ostream_t *file)
+{
+	unsigned char *buffer;
+	size_t diff, bufsz;
+	int ret;
+
+	if (file->sparse_count == 0)
+		return 0;
+
+	if (file->flags & SQFS_FILE_OPEN_NO_SPARSE) {
+		bufsz = file->sparse_count > 1024 ? 1024 : file->sparse_count;
+		buffer = calloc(1, bufsz);
+		if (buffer == NULL)
+			return SQFS_ERROR_ALLOC;
+
+		while (file->sparse_count > 0) {
+			diff = file->sparse_count > (off_t)bufsz ?
+				bufsz : (size_t)file->sparse_count;
+
+			ret = write_all(file, buffer, diff);
+			if (ret) {
+				int temp = errno;
+				free(buffer);
+				errno = temp;
+				return ret;
+			}
+
+			file->sparse_count -= diff;
+		}
+
+		free(buffer);
+	} else {
+		if (lseek(file->fd, file->sparse_count, SEEK_CUR) == (off_t)-1)
+			return SQFS_ERROR_IO;
+
+		if (ftruncate(file->fd, file->size) != 0)
+			return SQFS_ERROR_IO;
+
+		file->sparse_count = 0;
+	}
+
+	return 0;
+}
+
+static int file_append(sqfs_ostream_t *strm, const void *data, size_t size)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+	int ret;
+
+	if (size == 0 || data == NULL) {
+		file->sparse_count += size;
+		file->size += size;
+		return 0;
+	}
+
+	ret = realize_sparse(file);
+	if (ret)
+		return ret;
+
+	return write_all(file, data, size);
+}
+
+static int file_flush(sqfs_ostream_t *strm)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+	int ret;
+
+	ret = realize_sparse(file);
+	if (ret)
+		return ret;
+
+	if (fsync(file->fd) != 0) {
+		if (errno != EINVAL)
+			return SQFS_ERROR_IO;
+	}
+
+	return 0;
+}
+
+static void file_destroy(sqfs_object_t *obj)
+{
+	file_ostream_t *file = (file_ostream_t *)obj;
+
+	close(file->fd);
+	free(file->path);
+	free(file);
+}
+
+static const char *file_get_filename(sqfs_ostream_t *strm)
+{
+	return ((file_ostream_t *)strm)->path;
+}
+
+int sqfs_ostream_open_handle(sqfs_ostream_t **out, const char *path,
+			     sqfs_file_handle_t fd, int flags)
+{
+	file_ostream_t *file = calloc(1, sizeof(*file));
+	sqfs_ostream_t *strm = (sqfs_ostream_t *)file;
+
+	*out = NULL;
+	if (file == NULL)
+		return SQFS_ERROR_ALLOC;
+
+	sqfs_object_init(file, file_destroy, NULL);
+
+	file->path = strdup(path);
+	if (file->path == NULL) {
+		int temp = errno;
+		free(file);
+		errno = temp;
+		return SQFS_ERROR_ALLOC;
+	}
+
+	file->fd = dup(fd);
+	if (file->fd < 0) {
+		int temp = errno;
+		free(file->path);
+		free(file);
+		errno = temp;
+		return SQFS_ERROR_IO;
+	}
+
+	close(fd);
+
+	file->flags = flags;
+	strm->append = file_append;
+	strm->flush = file_flush;
+	strm->get_filename = file_get_filename;
+
+	*out = strm;
+	return 0;
+}
+
+int sqfs_ostream_open_file(sqfs_ostream_t **out, const char *path, int flags)
+{
+	sqfs_file_handle_t fd;
+	int ret;
+
+	*out = NULL;
+	ret = sqfs_open_native_file(&fd, path, flags);
+	if (ret)
+		return ret;
+
+	ret = sqfs_ostream_open_handle(out, path, fd, flags);
+	if (ret) {
+		int temp = errno;
+		close(fd);
+		errno = temp;
+		return ret;
+	}
+
+	return 0;
+}
diff --git a/lib/sqfs/src/win32/istream.c b/lib/sqfs/src/win32/istream.c
new file mode 100644
index 0000000..ba44c0b
--- /dev/null
+++ b/lib/sqfs/src/win32/istream.c
@@ -0,0 +1,179 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * istream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "config.h"
+
+#include "sqfs/io.h"
+#include "sqfs/error.h"
+
+#define BUFSZ (131072)
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <assert.h>
+
+typedef struct {
+	sqfs_istream_t base;
+	char *path;
+	HANDLE hnd;
+
+	bool eof;
+	size_t buffer_offset;
+	size_t buffer_used;
+	sqfs_u8 buffer[BUFSZ];
+} file_istream_t;
+
+static int precache(sqfs_istream_t *strm)
+{
+	file_istream_t *file = (file_istream_t *)strm;
+	DWORD diff, actual;
+
+	if (file->eof)
+		return 0;
+
+	if (file->buffer_offset > 0 &&
+	    file->buffer_offset < file->buffer_used) {
+		memmove(file->buffer, file->buffer + file->buffer_offset,
+			file->buffer_used - file->buffer_offset);
+	}
+
+	file->buffer_used -= file->buffer_offset;
+	file->buffer_offset = 0;
+
+	while (file->buffer_used < sizeof(file->buffer)) {
+		diff = sizeof(file->buffer) - file->buffer_used;
+
+		if (!ReadFile(file->hnd, file->buffer + file->buffer_used,
+			      diff, &actual, NULL)) {
+			DWORD error = GetLastError();
+
+			if (error == ERROR_HANDLE_EOF ||
+			    error == ERROR_BROKEN_PIPE) {
+				file->eof = true;
+				break;
+			}
+
+			SetLastError(error);
+			return SQFS_ERROR_IO;
+		}
+
+		if (actual == 0) {
+			file->eof = true;
+			break;
+		}
+
+		file->buffer_used += actual;
+	}
+
+	return 0;
+}
+
+static int file_get_buffered_data(sqfs_istream_t *strm, const sqfs_u8 **out,
+				  size_t *size, size_t want)
+{
+	file_istream_t *file = (file_istream_t *)strm;
+
+	if (want > BUFSZ)
+		want = BUFSZ;
+
+	if (file->buffer_used == 0 ||
+	    (file->buffer_used - file->buffer_offset) < want) {
+		int ret = precache(strm);
+		if (ret)
+			return ret;
+	}
+
+	*out = file->buffer + file->buffer_offset;
+	*size = file->buffer_used - file->buffer_offset;
+	return (file->eof && *size == 0) ? 1 : 0;
+}
+
+static void file_advance_buffer(sqfs_istream_t *strm, size_t count)
+{
+	file_istream_t *file = (file_istream_t *)strm;
+
+	assert(count <= file->buffer_used);
+
+	file->buffer_offset += count;
+
+	assert(file->buffer_offset <= file->buffer_used);
+}
+
+static const char *file_get_filename(sqfs_istream_t *strm)
+{
+	return ((file_istream_t *)strm)->path;
+}
+
+static void file_destroy(sqfs_object_t *obj)
+{
+	file_istream_t *file = (file_istream_t *)obj;
+
+	CloseHandle(file->hnd);
+	free(file->path);
+	free(file);
+}
+
+int sqfs_istream_open_handle(sqfs_istream_t **out, const char *path,
+			     sqfs_file_handle_t hnd)
+{
+	file_istream_t *file = calloc(1, sizeof(*file));
+	sqfs_istream_t *strm = (sqfs_istream_t *)file;
+	BOOL ret;
+
+	if (file == NULL)
+		return SQFS_ERROR_ALLOC;
+
+	sqfs_object_init(file, file_destroy, NULL);
+
+	file->path = strdup(path);
+	if (file->path == NULL) {
+		DWORD temp = GetLastError();
+		free(file);
+		SetLastError(temp);
+		return SQFS_ERROR_ALLOC;
+	}
+
+	ret = DuplicateHandle(GetCurrentProcess(), hnd,
+			      GetCurrentProcess(), &file->hnd,
+			      0, FALSE, DUPLICATE_SAME_ACCESS);
+	if (!ret) {
+		DWORD temp = GetLastError();
+		free(file->path);
+		free(file);
+		SetLastError(temp);
+		return SQFS_ERROR_IO;
+	}
+
+	CloseHandle(hnd);
+
+	strm->get_buffered_data = file_get_buffered_data;
+	strm->advance_buffer = file_advance_buffer;
+	strm->get_filename = file_get_filename;
+
+	*out = strm;
+	return 0;
+}
+
+int sqfs_istream_open_file(sqfs_istream_t **out, const char *path)
+{
+	sqfs_file_handle_t hnd;
+	int ret;
+
+	ret = sqfs_open_native_file(&hnd, path, SQFS_FILE_OPEN_READ_ONLY);
+	if (ret)
+		return ret;
+
+	ret = sqfs_istream_open_handle(out, path, hnd);
+	if (ret) {
+		DWORD temp = GetLastError();
+		CloseHandle(hnd);
+		SetLastError(temp);
+		return ret;
+	}
+
+	return 0;
+}
diff --git a/lib/sqfs/src/win32/ostream.c b/lib/sqfs/src/win32/ostream.c
new file mode 100644
index 0000000..3e6a8a7
--- /dev/null
+++ b/lib/sqfs/src/win32/ostream.c
@@ -0,0 +1,192 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * ostream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "config.h"
+
+#include "sqfs/io.h"
+#include "sqfs/error.h"
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+typedef struct {
+	sqfs_ostream_t base;
+	sqfs_u64 sparse_count;
+	char *path;
+	HANDLE hnd;
+	int flags;
+} file_ostream_t;
+
+static int write_data(file_ostream_t *file, const void *data, size_t size)
+{
+	DWORD diff;
+
+	while (size > 0) {
+		if (!WriteFile(file->hnd, data, size, &diff, NULL))
+			return SQFS_ERROR_IO;
+
+		size -= diff;
+		data = (const char *)data + diff;
+	}
+
+	return 0;
+}
+
+static int realize_sparse(file_ostream_t *file)
+{
+	size_t bufsz, diff;
+	LARGE_INTEGER pos;
+	void *buffer;
+	int ret;
+
+	if (file->sparse_count == 0)
+		return 0;
+
+	if (file->flags & SQFS_FILE_OPEN_NO_SPARSE) {
+		bufsz = file->sparse_count > 1024 ? 1024 : file->sparse_count;
+		buffer = calloc(1, bufsz);
+
+		if (buffer == NULL)
+			return SQFS_ERROR_ALLOC;
+
+		while (file->sparse_count > 0) {
+			diff = file->sparse_count > bufsz ?
+				bufsz : file->sparse_count;
+
+			ret = write_data(file, buffer, diff);
+			if (ret) {
+				DWORD temp = GetLastError();
+				free(buffer);
+				SetLastError(temp);
+				return ret;
+			}
+
+			file->sparse_count -= diff;
+		}
+
+		free(buffer);
+	} else {
+		pos.QuadPart = file->sparse_count;
+
+		if (!SetFilePointerEx(file->hnd, pos, NULL, FILE_CURRENT))
+			return SQFS_ERROR_IO;
+
+		if (!SetEndOfFile(file->hnd))
+			return SQFS_ERROR_IO;
+
+		file->sparse_count = 0;
+	}
+
+	return 0;
+}
+
+static int file_append(sqfs_ostream_t *strm, const void *data, size_t size)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+	int ret;
+
+	if (size == 0 || data == NULL) {
+		file->sparse_count += size;
+		return 0;
+	}
+
+	ret = realize_sparse(file);
+	if (ret)
+		return ret;
+
+	return write_data(file, data, size);
+}
+
+static int file_flush(sqfs_ostream_t *strm)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+	int ret;
+
+	ret = realize_sparse(file);
+	if (ret)
+		return ret;
+
+	if (!FlushFileBuffers(file->hnd))
+		return SQFS_ERROR_IO;
+
+	return 0;
+}
+
+static void file_destroy(sqfs_object_t *obj)
+{
+	file_ostream_t *file = (file_ostream_t *)obj;
+
+	CloseHandle(file->hnd);
+	free(file->path);
+	free(file);
+}
+
+static const char *file_get_filename(sqfs_ostream_t *strm)
+{
+	return ((file_ostream_t *)strm)->path;
+}
+
+int sqfs_ostream_open_handle(sqfs_ostream_t **out, const char *path,
+			     sqfs_file_handle_t hnd, int flags)
+{
+	file_ostream_t *file = calloc(1, sizeof(*file));
+	sqfs_ostream_t *strm = (sqfs_ostream_t *)file;
+	BOOL ret;
+
+	if (file == NULL)
+		return SQFS_ERROR_ALLOC;
+
+	sqfs_object_init(file, file_destroy, NULL);
+
+	file->path = strdup(path);
+	if (file->path == NULL) {
+		free(file);
+		return SQFS_ERROR_ALLOC;
+	}
+
+	ret = DuplicateHandle(GetCurrentProcess(), hnd,
+			      GetCurrentProcess(), &file->hnd,
+			      0, FALSE, DUPLICATE_SAME_ACCESS);
+	if (!ret) {
+		DWORD temp = GetLastError();
+		free(file->path);
+		free(file);
+		SetLastError(temp);
+		return SQFS_ERROR_IO;
+	}
+
+	CloseHandle(hnd);
+
+	file->flags = flags;
+	strm->append = file_append;
+	strm->flush = file_flush;
+	strm->get_filename = file_get_filename;
+
+	*out = strm;
+	return 0;
+}
+
+int sqfs_ostream_open_file(sqfs_ostream_t **out, const char *path, int flags)
+{
+	sqfs_file_handle_t hnd;
+	int ret;
+
+	*out = NULL;
+	ret = sqfs_open_native_file(&hnd, path, flags);
+	if (ret)
+		return ret;
+
+	ret = sqfs_ostream_open_handle(out, path, hnd, flags);
+	if (ret) {
+		DWORD temp = GetLastError();
+		CloseHandle(hnd);
+		SetLastError(temp);
+		return SQFS_ERROR_IO;
+	}
+
+	return 0;
+}