11 files changed, 1216 insertions, 0 deletions

diff --git a/lib/io/src/get_line.c b/lib/io/src/get_line.c
new file mode 100644
index 0000000..f7e0b59
--- /dev/null
+++ b/lib/io/src/get_line.c
@@ -0,0 +1,118 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * get_line.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "internal.h"
+
+static void ltrim(char *buffer)
+{
+	size_t i = 0;
+
+	while (isspace(buffer[i]))
+		++i;
+
+	if (i > 0)
+		memmove(buffer, buffer + i, strlen(buffer + i) + 1);
+}
+
+static void rtrim(char *buffer)
+{
+	size_t i = strlen(buffer);
+
+	while (i > 0 && isspace(buffer[i - 1]))
+		--i;
+
+	buffer[i] = '\0';
+}
+
+static size_t trim(char *buffer, int flags)
+{
+	if (flags & ISTREAM_LINE_LTRIM)
+		ltrim(buffer);
+
+	if (flags & ISTREAM_LINE_RTRIM)
+		rtrim(buffer);
+
+	return strlen(buffer);
+}
+
+int istream_get_line(istream_t *strm, char **out,
+		     size_t *line_num, int flags)
+{
+	char *line = NULL, *new;
+	size_t i, line_len = 0;
+	bool have_line = false;
+
+	*out = NULL;
+
+	for (;;) {
+		if (istream_precache(strm))
+			return -1;
+
+		if (strm->buffer_used == 0) {
+			if (line_len == 0)
+				goto out_eof;
+
+			line_len = trim(line, flags);
+
+			if (line_len == 0 &&
+			    (flags & ISTREAM_LINE_SKIP_EMPTY)) {
+				goto out_eof;
+			}
+			break;
+		}
+
+		for (i = 0; i < strm->buffer_used; ++i) {
+			if (strm->buffer[i] == '\n')
+				break;
+		}
+
+		if (i < strm->buffer_used) {
+			have_line = true;
+			strm->buffer_offset = i + 1;
+
+			if (i > 0 && strm->buffer[i - 1] == '\r')
+				--i;
+		} else {
+			strm->buffer_offset = i;
+		}
+
+		new = realloc(line, line_len + i + 1);
+		if (new == NULL)
+			goto fail_errno;
+
+		line = new;
+		memcpy(line + line_len, strm->buffer, i);
+		line_len += i;
+		line[line_len] = '\0';
+
+		if (have_line) {
+			line_len = trim(line, flags);
+
+			if (line_len == 0 &&
+			    (flags & ISTREAM_LINE_SKIP_EMPTY)) {
+				free(line);
+				line = NULL;
+				have_line = false;
+				*line_num += 1;
+				continue;
+			}
+			break;
+		}
+	}
+
+	*out = line;
+	return 0;
+fail_errno:
+	fprintf(stderr, "%s: " PRI_SZ ": %s.\n", strm->get_filename(strm),
+		*line_num, strerror(errno));
+	free(line);
+	*out = NULL;
+	return -1;
+out_eof:
+	free(line);
+	*out = NULL;
+	return 1;
+}
diff --git a/lib/io/src/internal.h b/lib/io/src/internal.h
new file mode 100644
index 0000000..25a0196
--- /dev/null
+++ b/lib/io/src/internal.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * internal.h
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#ifndef INTERNAL_H
+#define INTERNAL_H
+
+#include "config.h"
+#include "compat.h"
+#include "io/istream.h"
+#include "io/ostream.h"
+#include "io/file.h"
+#include "io/xfrm.h"
+#include "io/std.h"
+#include "xfrm/compress.h"
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+
+#define BUFSZ (262144)
+
+#endif /* INTERNAL_H */
diff --git a/lib/io/src/istream.c b/lib/io/src/istream.c
new file mode 100644
index 0000000..64fa478
--- /dev/null
+++ b/lib/io/src/istream.c
@@ -0,0 +1,86 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * istream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "internal.h"
+
+
+sqfs_s32 istream_read(istream_t *strm, void *data, size_t size)
+{
+	sqfs_s32 total = 0;
+	size_t diff;
+
+	if (size > 0x7FFFFFFF)
+		size = 0x7FFFFFFF;
+
+	while (size > 0) {
+		if (strm->buffer_offset >= strm->buffer_used) {
+			if (istream_precache(strm))
+				return -1;
+
+			if (strm->buffer_used == 0)
+				break;
+		}
+
+		diff = strm->buffer_used - strm->buffer_offset;
+		if (diff > size)
+			diff = size;
+
+		memcpy(data, strm->buffer + strm->buffer_offset, diff);
+		data = (char *)data + diff;
+		strm->buffer_offset += diff;
+		size -= diff;
+		total += diff;
+	}
+
+	return total;
+}
+
+int istream_precache(istream_t *strm)
+{
+	if (strm->buffer_offset >= strm->buffer_used) {
+		strm->buffer_offset = 0;
+		strm->buffer_used = 0;
+	} else if (strm->buffer_offset > 0) {
+		memmove(strm->buffer,
+			strm->buffer + strm->buffer_offset,
+			strm->buffer_used - strm->buffer_offset);
+
+		strm->buffer_used -= strm->buffer_offset;
+		strm->buffer_offset = 0;
+	}
+
+	if (strm->eof)
+		return 0;
+
+	return strm->precache(strm);
+}
+
+int istream_skip(istream_t *strm, sqfs_u64 size)
+{
+	size_t diff;
+
+	while (size > 0) {
+		if (strm->buffer_offset >= strm->buffer_used) {
+			if (istream_precache(strm))
+				return -1;
+
+			if (strm->buffer_used == 0) {
+				fprintf(stderr, "%s: unexpected end-of-file\n",
+					strm->get_filename(strm));
+				return -1;
+			}
+		}
+
+		diff = strm->buffer_used - strm->buffer_offset;
+		if ((sqfs_u64)diff > size)
+			diff = size;
+
+		strm->buffer_offset += diff;
+		size -= diff;
+	}
+
+	return 0;
+}
diff --git a/lib/io/src/ostream.c b/lib/io/src/ostream.c
new file mode 100644
index 0000000..da0b7b3
--- /dev/null
+++ b/lib/io/src/ostream.c
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * ostream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "internal.h"
+
+
+static int append_sparse_fallback(ostream_t *strm, size_t size)
+{
+	char buffer[512];
+	size_t diff;
+
+	memset(buffer, 0, sizeof(buffer));
+
+	while (size > 0) {
+		diff = size < sizeof(buffer) ? size : sizeof(buffer);
+
+		if (strm->append(strm, buffer, diff))
+			return -1;
+
+		size -= diff;
+	}
+
+	return 0;
+}
+
+int ostream_append_sparse(ostream_t *strm, size_t size)
+{
+	if (strm->append_sparse == NULL)
+		return append_sparse_fallback(strm, size);
+
+	return strm->append_sparse(strm, size);
+}
+
+sqfs_s32 ostream_append_from_istream(ostream_t *out, istream_t *in,
+				     sqfs_u32 size)
+{
+	sqfs_s32 total = 0;
+	size_t diff;
+
+	if (size > 0x7FFFFFFF)
+		size = 0x7FFFFFFF;
+
+	while (size > 0) {
+		if (in->buffer_offset >= in->buffer_used) {
+			if (istream_precache(in))
+				return -1;
+
+			if (in->buffer_used == 0)
+				break;
+		}
+
+		diff = in->buffer_used - in->buffer_offset;
+		if (diff > size)
+			diff = size;
+
+		if (out->append(out, in->buffer + in->buffer_offset, diff))
+			return -1;
+
+		in->buffer_offset += diff;
+		size -= diff;
+		total += diff;
+	}
+
+	return total;
+}
diff --git a/lib/io/src/printf.c b/lib/io/src/printf.c
new file mode 100644
index 0000000..3850487
--- /dev/null
+++ b/lib/io/src/printf.c
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * printf.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "internal.h"
+
+int ostream_printf(ostream_t *strm, const char *fmt, ...)
+{
+	char *temp = NULL;
+	va_list ap;
+	int ret;
+
+	va_start(ap, fmt);
+
+	ret = vasprintf(&temp, fmt, ap);
+	if (ret < 0)
+		perror(strm->get_filename(strm));
+	va_end(ap);
+
+	if (ret < 0)
+		return -1;
+
+	if (strm->append(strm, temp, ret))
+		ret = -1;
+
+	free(temp);
+	return ret;
+}
diff --git a/lib/io/src/unix/istream.c b/lib/io/src/unix/istream.c
new file mode 100644
index 0000000..f8cffad
--- /dev/null
+++ b/lib/io/src/unix/istream.c
@@ -0,0 +1,123 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * istream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "../internal.h"
+
+typedef struct {
+	istream_t base;
+	char *path;
+	int fd;
+
+	sqfs_u8 buffer[BUFSZ];
+} file_istream_t;
+
+static int file_precache(istream_t *strm)
+{
+	file_istream_t *file = (file_istream_t *)strm;
+	ssize_t ret;
+	size_t diff;
+
+	while (strm->buffer_used < sizeof(file->buffer)) {
+		diff = sizeof(file->buffer) - strm->buffer_used;
+
+		ret = read(file->fd, strm->buffer + strm->buffer_used, diff);
+
+		if (ret == 0) {
+			strm->eof = true;
+			break;
+		}
+
+		if (ret < 0) {
+			if (errno == EINTR)
+				continue;
+
+			perror(file->path);
+			return -1;
+		}
+
+		strm->buffer_used += ret;
+	}
+
+	return 0;
+}
+
+static const char *file_get_filename(istream_t *strm)
+{
+	file_istream_t *file = (file_istream_t *)strm;
+
+	return file->path;
+}
+
+static void file_destroy(sqfs_object_t *obj)
+{
+	file_istream_t *file = (file_istream_t *)obj;
+
+	if (file->fd != STDIN_FILENO)
+		close(file->fd);
+
+	free(file->path);
+	free(file);
+}
+
+istream_t *istream_open_file(const char *path)
+{
+	file_istream_t *file = calloc(1, sizeof(*file));
+	istream_t *strm = (istream_t *)file;
+
+	if (file == NULL) {
+		perror(path);
+		return NULL;
+	}
+
+	sqfs_object_init(file, file_destroy, NULL);
+
+	file->path = strdup(path);
+	if (file->path == NULL) {
+		perror(path);
+		goto fail_free;
+	}
+
+	file->fd = open(path, O_RDONLY);
+	if (file->fd < 0) {
+		perror(path);
+		goto fail_path;
+	}
+
+	strm->buffer = file->buffer;
+	strm->precache = file_precache;
+	strm->get_filename = file_get_filename;
+	return strm;
+fail_path:
+	free(file->path);
+fail_free:
+	free(file);
+	return NULL;
+}
+
+istream_t *istream_open_stdin(void)
+{
+	file_istream_t *file = calloc(1, sizeof(*file));
+	istream_t *strm = (istream_t *)file;
+
+	if (file == NULL)
+		goto fail;
+
+	sqfs_object_init(file, file_destroy, NULL);
+
+	file->path = strdup("stdin");
+	if (file->path == NULL)
+		goto fail;
+
+	file->fd = STDIN_FILENO;
+	strm->buffer = file->buffer;
+	strm->precache = file_precache;
+	strm->get_filename = file_get_filename;
+	return strm;
+fail:
+	perror("creating file wrapper for stdin");
+	free(file);
+	return NULL;
+}
diff --git a/lib/io/src/unix/ostream.c b/lib/io/src/unix/ostream.c
new file mode 100644
index 0000000..5ef2af2
--- /dev/null
+++ b/lib/io/src/unix/ostream.c
@@ -0,0 +1,173 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * ostream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "../internal.h"
+
+typedef struct {
+	ostream_t base;
+	char *path;
+	int fd;
+
+	off_t sparse_count;
+	off_t size;
+} file_ostream_t;
+
+static int file_append(ostream_t *strm, const void *data, size_t size)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+	ssize_t ret;
+
+	if (size == 0)
+		return 0;
+
+	if (file->sparse_count > 0) {
+		if (lseek(file->fd, file->sparse_count, SEEK_CUR) == (off_t)-1)
+			goto fail_errno;
+
+		file->sparse_count = 0;
+	}
+
+	while (size > 0) {
+		ret = write(file->fd, data, size);
+
+		if (ret == 0) {
+			fprintf(stderr, "%s: truncated data write.\n",
+				file->path);
+			return -1;
+		}
+
+		if (ret < 0) {
+			if (errno == EINTR)
+				continue;
+			goto fail_errno;
+		}
+
+		file->size += ret;
+		size -= ret;
+		data = (const char *)data + ret;
+	}
+
+	return 0;
+fail_errno:
+	perror(file->path);
+	return -1;
+}
+
+static int file_append_sparse(ostream_t *strm, size_t size)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+
+	file->sparse_count += size;
+	file->size += size;
+	return 0;
+}
+
+static int file_flush(ostream_t *strm)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+
+	if (file->sparse_count > 0) {
+		if (ftruncate(file->fd, file->size) != 0)
+			goto fail;
+	}
+
+	if (fsync(file->fd) != 0) {
+		if (errno == EINVAL)
+			return 0;
+		goto fail;
+	}
+
+	return 0;
+fail:
+	perror(file->path);
+	return -1;
+}
+
+static void file_destroy(sqfs_object_t *obj)
+{
+	file_ostream_t *file = (file_ostream_t *)obj;
+
+	if (file->fd != STDOUT_FILENO)
+		close(file->fd);
+
+	free(file->path);
+	free(file);
+}
+
+static const char *file_get_filename(ostream_t *strm)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+
+	return file->path;
+}
+
+ostream_t *ostream_open_file(const char *path, int flags)
+{
+	file_ostream_t *file = calloc(1, sizeof(*file));
+	ostream_t *strm = (ostream_t *)file;
+
+	if (file == NULL) {
+		perror(path);
+		return NULL;
+	}
+
+	sqfs_object_init(file, file_destroy, NULL);
+
+	file->path = strdup(path);
+	if (file->path == NULL) {
+		perror(path);
+		goto fail_free;
+	}
+
+	if (flags & OSTREAM_OPEN_OVERWRITE) {
+		file->fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
+	} else {
+		file->fd = open(path, O_WRONLY | O_CREAT | O_EXCL, 0644);
+	}
+
+	if (file->fd < 0) {
+		perror(path);
+		goto fail_path;
+	}
+
+	if (flags & OSTREAM_OPEN_SPARSE)
+		strm->append_sparse = file_append_sparse;
+
+	strm->append = file_append;
+	strm->flush = file_flush;
+	strm->get_filename = file_get_filename;
+	return strm;
+fail_path:
+	free(file->path);
+fail_free:
+	free(file);
+	return NULL;
+}
+
+ostream_t *ostream_open_stdout(void)
+{
+	file_ostream_t *file = calloc(1, sizeof(*file));
+	ostream_t *strm = (ostream_t *)file;
+
+	if (file == NULL)
+		goto fail;
+
+	file->path = strdup("stdout");
+	if (file->path == NULL)
+		goto fail;
+
+	file->fd = STDOUT_FILENO;
+	strm->append = file_append;
+	strm->flush = file_flush;
+	strm->get_filename = file_get_filename;
+
+	sqfs_object_init(file, file_destroy, NULL);
+	return strm;
+fail:
+	perror("creating file wrapper for stdout");
+	free(file);
+	return NULL;
+}
diff --git a/lib/io/src/win32/istream.c b/lib/io/src/win32/istream.c
new file mode 100644
index 0000000..be3d829
--- /dev/null
+++ b/lib/io/src/win32/istream.c
@@ -0,0 +1,138 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * istream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "../internal.h"
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+typedef struct {
+	istream_t base;
+	char *path;
+	HANDLE hnd;
+
+	sqfs_u8 buffer[BUFSZ];
+} file_istream_t;
+
+static int file_precache(istream_t *strm)
+{
+	file_istream_t *file = (file_istream_t *)strm;
+	DWORD diff, actual;
+	HANDLE hnd;
+
+	hnd = file->path == NULL ? GetStdHandle(STD_INPUT_HANDLE) : file->hnd;
+
+	while (strm->buffer_used < sizeof(file->buffer)) {
+		diff = sizeof(file->buffer) - strm->buffer_used;
+
+		if (!ReadFile(hnd, strm->buffer + strm->buffer_used,
+			      diff, &actual, NULL)) {
+			DWORD error = GetLastError();
+
+			if (error == ERROR_HANDLE_EOF ||
+			    error == ERROR_BROKEN_PIPE) {
+				strm->eof = true;
+				break;
+			}
+
+			SetLastError(error);
+
+			w32_perror(file->path == NULL ? "stdin" : file->path);
+			return -1;
+		}
+
+		if (actual == 0) {
+			strm->eof = true;
+			break;
+		}
+
+		strm->buffer_used += actual;
+	}
+
+	return 0;
+}
+
+static const char *file_get_filename(istream_t *strm)
+{
+	file_istream_t *file = (file_istream_t *)strm;
+
+	return file->path == NULL ? "stdin" : file->path;
+}
+
+static void file_destroy(sqfs_object_t *obj)
+{
+	file_istream_t *file = (file_istream_t *)obj;
+
+	if (file->path != NULL) {
+		CloseHandle(file->hnd);
+		free(file->path);
+	}
+
+	free(file);
+}
+
+istream_t *istream_open_file(const char *path)
+{
+	file_istream_t *file = calloc(1, sizeof(*file));
+	istream_t *strm = (istream_t *)file;
+	WCHAR *wpath = NULL;
+
+	if (file == NULL) {
+		perror(path);
+		return NULL;
+	}
+
+	sqfs_object_init(file, file_destroy, NULL);
+
+	wpath = path_to_windows(path);
+	if (wpath == NULL)
+		goto fail_free;
+
+	file->path = strdup(path);
+	if (file->path == NULL) {
+		perror(path);
+		goto fail_free;
+	}
+
+	file->hnd = CreateFileW(wpath, GENERIC_READ, FILE_SHARE_READ, NULL,
+			       OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
+
+	if (file->hnd == INVALID_HANDLE_VALUE) {
+		perror(path);
+		goto fail_path;
+	}
+
+	free(wpath);
+
+	strm->buffer = file->buffer;
+	strm->precache = file_precache;
+	strm->get_filename = file_get_filename;
+	return strm;
+fail_path:
+	free(file->path);
+fail_free:
+	free(wpath);
+	free(file);
+	return NULL;
+}
+
+istream_t *istream_open_stdin(void)
+{
+	file_istream_t *file = calloc(1, sizeof(*file));
+	istream_t *strm = (istream_t *)file;
+
+	if (file == NULL) {
+		perror("stdin");
+		return NULL;
+	}
+
+	sqfs_object_init(file, file_destroy, NULL);
+
+	strm->buffer = file->buffer;
+	strm->precache = file_precache;
+	strm->get_filename = file_get_filename;
+	return strm;
+}
diff --git a/lib/io/src/win32/ostream.c b/lib/io/src/win32/ostream.c
new file mode 100644
index 0000000..0fe04f3
--- /dev/null
+++ b/lib/io/src/win32/ostream.c
@@ -0,0 +1,199 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * ostream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "../internal.h"
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+typedef struct {
+	ostream_t base;
+	char *path;
+	HANDLE hnd;
+} file_ostream_t;
+
+static int w32_append(HANDLE hnd, const char *filename,
+		      const void *data, size_t size)
+{
+	DWORD diff;
+
+	while (size > 0) {
+		if (!WriteFile(hnd, data, size, &diff, NULL)) {
+			w32_perror(filename);
+			return -1;
+		}
+
+		size -= diff;
+		data = (const char *)data + diff;
+	}
+
+	return 0;
+}
+
+static int w32_flush(HANDLE hnd, const char *filename)
+{
+	if (!FlushFileBuffers(hnd)) {
+		w32_perror(filename);
+		return -1;
+	}
+
+	return 0;
+}
+
+/*****************************************************************************/
+
+static int file_append(ostream_t *strm, const void *data, size_t size)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+
+	return w32_append(file->hnd, file->path, data, size);
+}
+
+static int file_append_sparse(ostream_t *strm, size_t size)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+	LARGE_INTEGER pos;
+
+	pos.QuadPart = size;
+
+	if (!SetFilePointerEx(file->hnd, pos, NULL, FILE_CURRENT))
+		goto fail;
+
+	if (!SetEndOfFile(file->hnd))
+		goto fail;
+
+	return 0;
+fail:
+	w32_perror(file->path);
+	return -1;
+}
+
+static int file_flush(ostream_t *strm)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+
+	return w32_flush(file->hnd, file->path);
+}
+
+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(ostream_t *strm)
+{
+	file_ostream_t *file = (file_ostream_t *)strm;
+
+	return file->path;
+}
+
+/*****************************************************************************/
+
+static int stdout_append(ostream_t *strm, const void *data, size_t size)
+{
+	(void)strm;
+	return w32_append(GetStdHandle(STD_OUTPUT_HANDLE), "stdout",
+			  data, size);
+}
+
+static int stdout_flush(ostream_t *strm)
+{
+	(void)strm;
+	return w32_flush(GetStdHandle(STD_OUTPUT_HANDLE), "stdout");
+}
+
+static void stdout_destroy(sqfs_object_t *obj)
+{
+	free(obj);
+}
+
+static const char *stdout_get_filename(ostream_t *strm)
+{
+	(void)strm;
+	return "stdout";
+}
+
+/*****************************************************************************/
+
+ostream_t *ostream_open_file(const char *path, int flags)
+{
+	file_ostream_t *file = calloc(1, sizeof(*file));
+	sqfs_object_t *obj = (sqfs_object_t *)file;
+	ostream_t *strm = (ostream_t *)file;
+	int access_flags, creation_mode;
+	WCHAR *wpath = NULL;
+
+	if (file == NULL) {
+		perror(path);
+		return NULL;
+	}
+
+	sqfs_object_init(file, file_destroy, NULL);
+
+	wpath = path_to_windows(path);
+	if (wpath == NULL)
+		goto fail_free;
+
+	file->path = strdup(path);
+	if (file->path == NULL) {
+		perror(path);
+		goto fail_free;
+	}
+
+	access_flags = GENERIC_WRITE;
+
+	if (flags & OSTREAM_OPEN_OVERWRITE) {
+		creation_mode = CREATE_ALWAYS;
+	} else {
+		creation_mode = CREATE_NEW;
+	}
+
+	file->hnd = CreateFileW(wpath, access_flags, 0, NULL, creation_mode,
+				FILE_ATTRIBUTE_NORMAL, NULL);
+
+	if (file->hnd == INVALID_HANDLE_VALUE) {
+		w32_perror(path);
+		goto fail_path;
+	}
+
+	free(wpath);
+
+	if (flags & OSTREAM_OPEN_SPARSE)
+		strm->append_sparse = file_append_sparse;
+
+	strm->append = file_append;
+	strm->flush = file_flush;
+	strm->get_filename = file_get_filename;
+	return strm;
+fail_path:
+	free(file->path);
+fail_free:
+	free(file);
+	free(wpath);
+	return NULL;
+}
+
+ostream_t *ostream_open_stdout(void)
+{
+	ostream_t *strm = calloc(1, sizeof(*strm));
+	sqfs_object_t *obj = (sqfs_object_t *)strm;
+
+	if (strm == NULL) {
+		perror("creating stdout file wrapper");
+		return NULL;
+	}
+
+	sqfs_object_init(strm, stdout_destroy, NULL);
+
+	strm->append = stdout_append;
+	strm->flush = stdout_flush;
+	strm->get_filename = stdout_get_filename;
+	return strm;
+}
diff --git a/lib/io/src/xfrm/istream.c b/lib/io/src/xfrm/istream.c
new file mode 100644
index 0000000..4a1ad77
--- /dev/null
+++ b/lib/io/src/xfrm/istream.c
@@ -0,0 +1,106 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * istream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "../internal.h"
+
+typedef struct istream_xfrm_t {
+	istream_t base;
+
+	istream_t *wrapped;
+	xfrm_stream_t *xfrm;
+
+	sqfs_u8 uncompressed[BUFSZ];
+} istream_xfrm_t;
+
+static int xfrm_precache(istream_t *base)
+{
+	istream_xfrm_t *xfrm = (istream_xfrm_t *)base;
+	int ret;
+
+	ret = istream_precache(xfrm->wrapped);
+	if (ret != 0)
+		return ret;
+
+	for (;;) {
+		const sqfs_u32 in_sz = xfrm->wrapped->buffer_used;
+		const sqfs_u32 out_sz = sizeof(xfrm->uncompressed);
+		sqfs_u32 in_off = 0, out_off = base->buffer_used;
+		int mode = XFRM_STREAM_FLUSH_NONE;
+
+		if (xfrm->wrapped->eof)
+			mode = XFRM_STREAM_FLUSH_FULL;
+
+		ret = xfrm->xfrm->process_data(xfrm->xfrm,
+					       xfrm->wrapped->buffer, in_sz,
+					       base->buffer + out_off,
+					       out_sz - out_off,
+					       &in_off, &out_off, mode);
+
+		if (ret == XFRM_STREAM_ERROR) {
+			fprintf(stderr, "%s: internal error in decompressor.\n",
+				base->get_filename(base));
+			return -1;
+		}
+
+		base->buffer_used = out_off;
+		xfrm->wrapped->buffer_offset = in_off;
+
+		if (ret == XFRM_STREAM_BUFFER_FULL || out_off >= out_sz)
+			break;
+
+		ret = istream_precache(xfrm->wrapped);
+		if (ret != 0)
+			return ret;
+
+		if (xfrm->wrapped->eof && xfrm->wrapped->buffer_used == 0) {
+			if (base->buffer_used == 0)
+				base->eof = true;
+			break;
+		}
+	}
+
+	return 0;
+}
+
+static const char *xfrm_get_filename(istream_t *strm)
+{
+	istream_xfrm_t *xfrm = (istream_xfrm_t *)strm;
+
+	return xfrm->wrapped->get_filename(xfrm->wrapped);
+}
+
+static void xfrm_destroy(sqfs_object_t *obj)
+{
+	istream_xfrm_t *xfrm = (istream_xfrm_t *)obj;
+
+	sqfs_drop(xfrm->xfrm);
+	sqfs_drop(xfrm->wrapped);
+	free(xfrm);
+}
+
+istream_t *istream_xfrm_create(istream_t *strm, xfrm_stream_t *xfrm)
+{
+	istream_xfrm_t *stream = calloc(1, sizeof(*stream));
+	istream_t *base = (istream_t *)stream;
+
+	if (stream == NULL)
+		goto fail;
+
+	sqfs_object_init(stream, xfrm_destroy, NULL);
+
+	stream->wrapped = sqfs_grab(strm);
+	stream->xfrm = sqfs_grab(xfrm);
+
+	base->precache = xfrm_precache;
+	base->get_filename = xfrm_get_filename;
+	base->buffer = stream->uncompressed;
+	base->eof = false;
+	return base;
+fail:
+	fprintf(stderr, "%s: error initializing decompressor stream.\n",
+		strm->get_filename(strm));
+	return NULL;
+}
diff --git a/lib/io/src/xfrm/ostream.c b/lib/io/src/xfrm/ostream.c
new file mode 100644
index 0000000..bd94515
--- /dev/null
+++ b/lib/io/src/xfrm/ostream.c
@@ -0,0 +1,144 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * ostream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "../internal.h"
+
+typedef struct ostream_xfrm_t {
+	ostream_t base;
+
+	ostream_t *wrapped;
+	xfrm_stream_t *xfrm;
+
+	size_t inbuf_used;
+
+	sqfs_u8 inbuf[BUFSZ];
+	sqfs_u8 outbuf[BUFSZ];
+} ostream_xfrm_t;
+
+static int flush_inbuf(ostream_xfrm_t *xfrm, bool finish)
+{
+	const sqfs_u32 avail_out = sizeof(xfrm->outbuf);
+	const sqfs_u32 avail_in = xfrm->inbuf_used;
+	const int mode = finish ? XFRM_STREAM_FLUSH_FULL :
+		XFRM_STREAM_FLUSH_NONE;
+	sqfs_u32 off_in = 0, off_out = 0;
+	int ret;
+
+	while (finish || off_in < avail_in) {
+		ret = xfrm->xfrm->process_data(xfrm->xfrm,
+					       xfrm->inbuf + off_in,
+					       avail_in - off_in,
+					       xfrm->outbuf + off_out,
+					       avail_out - off_out,
+					       &off_in, &off_out, mode);
+
+		if (ret == XFRM_STREAM_ERROR) {
+			fprintf(stderr,
+				"%s: internal error in compressor.\n",
+				xfrm->wrapped->get_filename(xfrm->wrapped));
+			return -1;
+		}
+
+		if (ostream_append(xfrm->wrapped, xfrm->outbuf, off_out))
+			return -1;
+
+		off_out = 0;
+
+		if (ret == XFRM_STREAM_END)
+			break;
+	}
+
+	if (off_out > 0) {
+		if (ostream_append(xfrm->wrapped, xfrm->outbuf, off_out))
+			return -1;
+	}
+
+	if (off_in < avail_in) {
+		memmove(xfrm->inbuf, xfrm->inbuf + off_in, avail_in - off_in);
+		xfrm->inbuf_used -= off_in;
+	} else {
+		xfrm->inbuf_used = 0;
+	}
+
+	return 0;
+}
+
+static int xfrm_append(ostream_t *strm, const void *data, size_t size)
+{
+	ostream_xfrm_t *xfrm = (ostream_xfrm_t *)strm;
+	size_t diff;
+
+	while (size > 0) {
+		if (xfrm->inbuf_used >= BUFSZ) {
+			if (flush_inbuf(xfrm, false))
+				return -1;
+		}
+
+		diff = BUFSZ - xfrm->inbuf_used;
+
+		if (diff > size)
+			diff = size;
+
+		memcpy(xfrm->inbuf + xfrm->inbuf_used, data, diff);
+
+		xfrm->inbuf_used += diff;
+		data = (const char *)data + diff;
+		size -= diff;
+	}
+
+	return 0;
+}
+
+static int xfrm_flush(ostream_t *strm)
+{
+	ostream_xfrm_t *xfrm = (ostream_xfrm_t *)strm;
+
+	if (xfrm->inbuf_used > 0) {
+		if (flush_inbuf(xfrm, true))
+			return -1;
+	}
+
+	return xfrm->wrapped->flush(xfrm->wrapped);
+}
+
+static const char *xfrm_get_filename(ostream_t *strm)
+{
+	ostream_xfrm_t *xfrm = (ostream_xfrm_t *)strm;
+
+	return xfrm->wrapped->get_filename(xfrm->wrapped);
+}
+
+static void xfrm_destroy(sqfs_object_t *obj)
+{
+	ostream_xfrm_t *xfrm = (ostream_xfrm_t *)obj;
+
+	sqfs_drop(xfrm->wrapped);
+	sqfs_drop(xfrm->xfrm);
+	free(xfrm);
+}
+
+ostream_t *ostream_xfrm_create(ostream_t *strm, xfrm_stream_t *xfrm)
+{
+	ostream_xfrm_t *stream = calloc(1, sizeof(*stream));
+	ostream_t *base = (ostream_t *)stream;
+
+	if (stream == NULL)
+		goto fail;
+
+	sqfs_object_init(stream, xfrm_destroy, NULL);
+
+	stream->wrapped = sqfs_grab(strm);
+	stream->xfrm = sqfs_grab(xfrm);
+	stream->inbuf_used = 0;
+	base->append = xfrm_append;
+	base->flush = xfrm_flush;
+	base->get_filename = xfrm_get_filename;
+	return base;
+fail:
+	fprintf(stderr, "%s: error initializing compressor.\n",
+		strm->get_filename(strm));
+	return NULL;
+}