/*

  * Copyright (C) 2008  Kristian Høgsberg <krh@redhat.com>

  * Copyright (C) 2008  Red Hat, Inc

  * Copyright (C) 2009, 2011, 2012, 2014, 2016  J. Ali Harlow <ali@juiblex.co.uk>

  *

  * This program is free software; you can redistribute it and/or modify

  * it under the terms of the GNU General Public License as published by

  * the Free Software Foundation; either version 2 of the License, or

  * (at your option) any later version.

  *

  * This program is distributed in the hope that it will be useful,

  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  * GNU General Public License for more details.

  *

  * You should have received a copy of the GNU General Public License along

  * with this program; if not, write to the Free Software Foundation, Inc.,

  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

  */

 #include "config.h"

 #include <limits.h>

 #include <string.h>

 #include <sys/types.h>

 #include <sys/stat.h>

 #include <stdlib.h>

 #include <stdio.h>

 #include <stdint.h>

 #include <errno.h>

 #include <unistd.h>

 #include <fcntl.h>

 #include <dirent.h>

 #ifdef MSWIN_API

 #include <windows.h>

 #include <direct.h>

 #endif

 #if HAVE_SYS_MMAN_H

 #include <sys/mman.h>

 #endif

 #include <assert.h>

 #include "razor.h"

 #include "types/types.h"

 #include "razor-internal.h"

 #ifndef O_BINARY

 #define O_BINARY	0

 #endif

 #define strcmp0(s1, s2)		((s1) && (s2) ? strcmp(s1, s2) : \

 				 (s1) ? 1 : (s2) ? -1 : 0)

 #define OPEN_FILE_USED		(1U<<0)

 #define OPEN_FILE_MMAPPED	(1U<<1)

 struct open_file {

 	void *addr;

 	size_t length;

 	uint32_t flags;

 };

 struct array open_files = { 0, };

 void *razor_file_get_contents(const char *filename, size_t *length, int private,

 			      struct razor_error **error)

 {

 	int fd;

 	struct stat st;

 	void *addr = NULL;

 	size_t nb;

 	ssize_t res;

 	struct open_file *of, *ofend;

 	fd = open(filename, O_RDONLY | O_BINARY);

 	if (fd < 0) {

 		razor_set_error_posix(error, filename);

 		return NULL;

 	}

 	if (fstat(fd, &st) < 0) {

 		razor_set_error_posix(error, filename);

 		close(fd);

 		return NULL;

 	}

 	*length = st.st_size;

 	ofend = open_files.data + open_files.size;

 	for (of = open_files.data; of < ofend; of++)

 		if (!(of->flags & OPEN_FILE_USED))

 			break;

 	if (of == ofend) {

 		of = array_add(&open_files, sizeof *of);

 		of->flags = 0;

 	}

 #if HAVE_SYS_MMAN_H

 	if (!private) {

 		addr = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);

 		if (addr == MAP_FAILED)

 			addr = NULL;

 		else

 			of->flags = OPEN_FILE_USED | OPEN_FILE_MMAPPED;

 	}

 #endif	/* HAVE_SYS_MMAN_H */

 	if (!addr) {

 		addr = malloc(st.st_size);

 		if (addr) {

 			of->flags = OPEN_FILE_USED;

 			nb = 0;

 			while(nb < st.st_size) {

 				res = read(fd, addr + nb, st.st_size - nb);

 				if (res <= 0) {

 					razor_set_error_posix(error, filename);

 					free(addr);

 					addr = NULL;

 					break;

 				}

 				nb += res;

 			}

 		} else

 			razor_set_error(error, RAZOR_POSIX_ERROR, ENOMEM, NULL,

 					"Not enough memory");

 	}

 	close(fd);

 	of->addr = addr;

 	of->length = st.st_size;

 	return addr;

 }

 int razor_file_free_contents(void *addr, size_t length)

 {

 #if HAVE_SYS_MMAN_H

 	int mmapped;

 #endif

 	struct open_file *of, *ofend;

 	ofend = open_files.data + open_files.size;

 	for (of = open_files.data; of < ofend; of++)

 		if ((of->flags & OPEN_FILE_USED) && of->addr == addr)

 			break;

 	if (of == ofend)

 		return -2;

 	length = of->length;

 #if HAVE_SYS_MMAN_H

 	mmapped = of->flags & OPEN_FILE_MMAPPED;

 #endif

 	of->flags &= ~OPEN_FILE_USED;

 	for (of = open_files.data; of < ofend; of++)

 		if (of->flags & OPEN_FILE_USED)

 			break;

 	if (of == ofend) {

 		array_release(&open_files);

 		array_init(&open_files);

 	}

 #if HAVE_SYS_MMAN_H

 	if (mmapped)

 		return munmap(addr, length);

 #endif

 	free(addr);

 	return 0;

 }

 int razor_file_mkdir(const char *path, mode_t mode, struct razor_error **error)

 {

 	int retval, code;

 	struct stat buf;

 	retval = mkdir(path, mode);

 	if (retval) {

 		/*

 		 * Ignore the case of a pre-existing directory and give

 		 * an explicit error message if there is something other

 		 * than a directory already at path.

 		 */

 		code = errno;

 		if (code != EEXIST || stat(path, &buf))

 			razor_set_error(error, RAZOR_POSIX_ERROR, code, path,

 					strerror(code));

 		else if (!S_ISDIR(buf.st_mode))

 			razor_set_error(error, RAZOR_POSIX_ERROR, code, path,

 					"Not a directory");

 	}

 	return retval;

 }

 int razor_file_unlink(const char *path, struct razor_error **error)

 {

 	int retval;

 	retval = unlink(path);

 	if (retval)

 		razor_set_error_posix(error, path);

 	return retval;

 }

 int razor_file_open(const char *path, int flags, mode_t mode,

 		    struct razor_error **error)

 {

 	int retval;

 	retval = open(path, flags, mode);

 	if (retval < 0)

 		razor_set_error_posix(error, path);

 	return retval;

 }

 int razor_file_move(const char *path, const char *dest,

 		    struct razor_error **error)

 {

 	int retval = 0;

 #ifdef MSWIN_API

 	wchar_t *oldbuf, *newbuf;

 	const DWORD flags = MOVEFILE_COPY_ALLOWED | MOVEFILE_REPLACE_EXISTING;

 	newbuf = razor_utf8_to_utf16(dest, -1);

 	oldbuf = razor_utf8_to_utf16(path, -1);

 	/*

 	 * Passing MOVEFILE_REPLACE_EXISTING to MoveFileEx() will

 	 * cover every case we care about _except_ replacing an empty

 	 * directory with a file. Calling RemoveDirectory() will deal

 	 * with this case while having no effect in all other cases.

 	 */

 	(void)RemoveDirectoryW(newbuf);

 	if (!MoveFileExW(oldbuf, newbuf, flags)) {

 		razor_set_error_mswin(error, newbuf, GetLastError());

 		retval = -1;

 	}

 	free(newbuf);

 	free(oldbuf);

 #else

 	int code;

 	const char *object;

 	if (rename(path, dest)) {

 		if (error) {

 			code = errno;

 			if (access(path, F_OK) < 0)

 				object = path;

 			else

 				object = dest;

 			razor_set_error(error, RAZOR_POSIX_ERROR, code, object, 

 					strerror(code));

 		}

 		retval = -1;

 	}

 #endif

 	return retval;

 }

 #ifndef MSWIN_API

 static char *absolute_path(const char *path)

 {

 	int len;

 	char *result, *subpath, *p, *s, *t;

 	result = realpath(path, NULL);

 	if (!result && errno == ENOENT) {

 		p = strdup(path);

 		s = strrchr(p, '/');

 		while (s) {

 			if (s == p) {

 				result = strdup("/");

 				break;

 			}

 			*s = '\0';

 			subpath = realpath(p, NULL);

 			if (subpath) {

 				*s = '/';

 				len = strlen(subpath);

 				result = malloc(len + strlen(s) + 1);

 				memcpy(result, subpath, len);

 				strcpy(result + len, s);

 				free(subpath);

 				break;

 			} else if (errno != ENOENT)

 				break;

 			t = strrchr(p, '/');

 			*s = '/';

 			s = t;

 		}

 		if (!s)

 			result = realpath(".", NULL);

 		free(p);

 	}

 	return result;

 }

 #endif

 int razor_file_is_directory(const char *path, struct razor_error **error)

 {

 	struct stat st;

 	if (stat(path, &st) < 0) {

 		razor_set_error_posix(error, path);

 		return -1;

 	}

 	return !!S_ISDIR(st.st_mode);

 }

 char *razor_file_mkdtemp_near(const char *path, const char *template,

 			      struct razor_error **error)

 {

 	char *retval;

 #ifdef MSWIN_API

 	if (path[0]=='\\' && path[1]=='\\' && path[2] && path[2]!='\\'

 	    && strchr(path+3,'\\')) {

 		/* We have a UNC path: \\servername\sharename... */

 		const char *sharename, *root;

 		int disklen;

 		sharename = strchr(path+3,'\\')+1;

 		root = strchr(sharename,'\\');

 		if (root)

 		    disklen = root - path;

 		else

 		    disklen = strlen(path);

 		retval = malloc(disklen + 1 + strlen(template) + 1);

 		memcpy(retval, path, disklen);

 		retval[disklen] = '\\';

 		strcpy(retval + disklen + 1, template);

 	} else if ((*path>='A' && *path<='Z' || *path>='a' && *path<='z') &&

 		    path[1]==':') {

 		retval = malloc(3 + strlen(template) + 1);

 		retval[0] = path[0];

 		retval[1] = ':';

 		retval[2] = '\\';

 		strcpy(retval + 3, template);

 	} else {

 		DWORD n;

 		wchar_t *buf;

 		char *dir;

 		n = GetCurrentDirectoryW(0, NULL);

 		buf = malloc(n * sizeof(wchar_t));

 		if (GetCurrentDirectoryW(n, buf)) {

 			dir = razor_utf16_to_utf8(buf, n - 1);

 			free(buf);

 			retval = razor_file_mkdtemp_near(dir, template, error);

 			free(dir);

 			return retval;

 		} else {

 			retval = malloc(3 + strlen(template) + 1);

 			retval[0] = 'C';

 			retval[1] = ':';

 			retval[2] = '\\';

 			strcpy(retval + 3, template);

 		}

 		free(buf);

 	}

 #else

 	/*

 	 * Find the mount point (assuming we can write to the

 	 * whole filesystem). Otherwise stop at the first

 	 * unwritable directory and take one step back.

 	 */

 	char *s, *abspath, saved;

 	int len, can_step_back = 0;

 	dev_t filesystem;

 	struct stat buf;

 	abspath = absolute_path(path);

 	if (!abspath) {

 		razor_set_error_posix(error, path);

 		return NULL;

 	}

 	if (stat(abspath, &buf) < 0) {

 		if (errno == ENOENT)

 			filesystem = 0;

 		else {

 			razor_set_error_posix(error, abspath);

 			free(abspath);

 			return NULL;

 		}

 	} else

 		filesystem = buf.st_dev;

 	len = strlen(abspath);

 	while(len > 1 && (s = strrchr(abspath, '/'))) {

 		if (s == abspath) {

 			saved = s[1];

 			s[1] = '\0';

 			len = s + 1 - abspath;

 		} else {

 			s[0] = '\0';

 			len = s - abspath;

 		}

 		if (stat(abspath, &buf) < 0) {

 			if (errno == ENOENT)

 				continue;

 			else {

 			    razor_set_error_posix(error, abspath);

 			    free(abspath);

 			    return NULL;

 			}

 		} else if (!filesystem)

 			filesystem = buf.st_dev;

 		if (buf.st_dev != filesystem || access(abspath, W_OK)) {

 			if (can_step_back) {

 				if (s == abspath)

 					s[1] = saved;

 				else

 					s[0] = '/';

 			}

 			len = strlen(abspath);

 			break;

 		} else

 			can_step_back = 1;

 	}

 	if (len == 1)

 		len = 0;	/* Avoid an unslightly double slash. */

 	retval = malloc(len + 1 + strlen(template) + 1);

 	memcpy(retval, abspath, len);

 	retval[len] = '/';

 	strcpy(retval + len + 1, template);

 	free(abspath);

 #endif

 	if (!mkdtemp(retval)) {

 		int err = errno;

 #ifdef EACCES

 		if (err == EACCES) {

 			char *s = strdup(template);

 #ifndef MSWIN_API

 			if (stat(".", &buf) < 0) {

 				razor_set_error_posix(error, ".");

 				free(s);

 				free(retval);

 				return NULL;

 			}

 			if (buf.st_dev != filesystem)

 				/*

 				 * Don't use a different filesystem. It will

 				 * only fail later on (in rename) and cause

 				 * an unhelpful error message (EXDEV).

 				 */

 				free(s);

 			else

 #endif

 			if (mkdtemp(s)) {

 				free(retval);

 				retval = s;

 				return retval;

 			} else

 				free(s);

 		}

 #endif

 		razor_set_error(error, RAZOR_POSIX_ERROR, err, retval,

 				strerror(err));

 		free(retval);

 		retval = NULL;

 	}

 	return retval;

 }

 struct open_dir {

 	uint32_t flags;

 #ifdef MSWIN_API

 	_WDIR *dp;

 	wchar_t *path2;

 #else

 	DIR *dp;

 	char *path;

 #endif

 };

 #define OPEN_DIR_USED		(1U<<0)

 struct array open_dirs = { 0, };

 void *razor_file_opendir(const char *path, struct razor_error **error)

 {

 	struct open_dir *od, *odend;

 	odend = open_dirs.data + open_dirs.size;

 	for (od = open_dirs.data; od < odend; od++)

 		if (!(od->flags & OPEN_DIR_USED))

 			break;

 	if (od == odend) {

 		od = array_add(&open_dirs, sizeof *od);

 		od->flags = 0;

 	}

 #ifdef MSWIN_API

 	od->path2 = razor_utf8_to_utf16(path, -1);

 	od->dp = _wopendir(od->path2);

 #else

 	od->path = strdup(path);

 	od->dp = opendir(od->path);

 #endif

 	if (!od->dp) {

 #ifdef MSWIN_API

 		razor_set_error_mswin(error, od->path2, GetLastError());

 		free(od->path2);

 #else

 		razor_set_error_posix(error, od->path);

 		free(od->path);

 #endif

 		return NULL;

 	}

 	od->flags = OPEN_DIR_USED;

 	return od;

 }

 char *razor_file_readdir(void *dp, struct razor_error **error)

 {

 	struct open_dir *od = dp, *odend;

 #ifdef MSWIN_API

 	struct _wdirent *dirp;

 	char *path;

 #else

 	struct dirent *dirp;

 #endif

 	odend = open_dirs.data + open_dirs.size;

 	if (dp < open_dirs.data || od >= odend || !(od->flags & OPEN_DIR_USED))

 		return (char *)-1;

 	errno = 0;

 #ifdef MSWIN_API

 	while((dirp = _wreaddir(od->dp))) {

 		path = razor_utf16_to_utf8(dirp->d_name, -1);

 		if (strcmp(path, ".") && strcmp(path, ".."))

 			return path;

 		else

 			free(path);

 	}

 #else

 	while((dirp = readdir(od->dp)))

 		if (strcmp(dirp->d_name, ".") && strcmp(dirp->d_name, ".."))

 			return strdup(dirp->d_name);

 #endif

 	if (errno) {

 #ifdef MSWIN_API

 		razor_set_error_mswin(error, od->path2, GetLastError());

 #else

 		razor_set_error_posix(error, od->path);

 #endif

 	}

 	return NULL;

 }

 int razor_file_closedir(void *dp, struct razor_error **error)

 {

 	struct open_dir *od = dp, *odend;

 	int retval;

 	odend = open_dirs.data + open_dirs.size;

 	if (dp < open_dirs.data || od >= odend || !(od->flags & OPEN_DIR_USED))

 		return -2;

 #ifdef MSWIN_API

 	/*

 	 * I can't find documentation to state that _wclosedir()

 	 * returns -1 on failure, so be paranoid.

 	 */

 	retval = _wclosedir(od->dp) ? -1 : 0;

 #else

 	retval = closedir(od->dp);

 #endif

 	if (retval) {

 #ifdef MSWIN_API

 		razor_set_error_mswin(error, od->path2, GetLastError());

 #else

 		razor_set_error_posix(error, od->path);

 #endif

 	}

 #ifdef MSWIN_API

 	free(od->path2);

 #else

 	free(od->path);

 #endif

 	od->flags &= ~OPEN_DIR_USED;

 	for (od = open_dirs.data; od < odend; od++)

 		if (od->flags & OPEN_DIR_USED)

 			break;

 	if (od == odend) {

 		array_release(&open_dirs);

 		array_init(&open_dirs);

 	}

 	return retval;

 }

 struct razor_uri_vtable_entry {

 	struct razor_uri_vtable vtable;

 	char *scheme;

 	struct array open_files, open_directories;

 };

 static struct array razor_uri_vtable_entries;

 static struct razor_uri_vtable_entry *

   razor_uri_get_vtable_entry(const char *scheme)

 {

 	struct razor_uri_vtable_entry *entry, *eend, *fallback = NULL;

 	eend = razor_uri_vtable_entries.data + razor_uri_vtable_entries.size;

 	for(entry = razor_uri_vtable_entries.data; entry < eend; entry++) {

 		if (!strcmp0(entry->scheme, scheme))

 			return entry;

 		else if (!entry->scheme)

 			fallback = entry;

 	}

 	return fallback;

 }

 int razor_uri_mkdir(const char *uri, mode_t mode, struct razor_error **error)

 {

 	int retval;

 	char *path;

 	struct razor_uri ru;

 	struct razor_uri_vtable_entry *entry;

 	struct razor_error *tmp_error = NULL;

 	if (razor_uri_parse(&ru, uri, error))

 		return -1;

 	path = razor_path_from_parsed_uri(&ru, &tmp_error);

 	if (razor_error_matches(tmp_error, RAZOR_GENERAL_ERROR,

 	    RAZOR_GENERAL_ERROR_UNSUPPORTED_URI))

 		razor_error_free(tmp_error);

 	else if (!path) {

 		razor_propagate_error(error, tmp_error, NULL);

 		razor_uri_destroy(&ru);

 		return -1;

 	}

 	if (path) {

 		razor_uri_destroy(&ru);

 		retval = razor_file_mkdir(path, mode, error);

 		free(path);

 	} else {

 		entry = razor_uri_get_vtable_entry(ru.scheme);

 		razor_uri_destroy(&ru);

 		if (!entry || !entry->vtable.mkdir) {

 			retval = -1;

 			razor_set_error(error, RAZOR_GENERAL_ERROR,

 					RAZOR_GENERAL_ERROR_UNSUPPORTED_URI,

 					uri, "No URI handler installed");

 		} else

 			retval = entry->vtable.mkdir(uri, mode, error);

 	}

 	return retval;

 }

 int razor_uri_unlink(const char *uri, struct razor_error **error)

 {

 	int retval;

 	char *path;

 	struct razor_uri ru;

 	struct razor_uri_vtable_entry *entry;

 	struct razor_error *tmp_error = NULL;

 	if (razor_uri_parse(&ru, uri, error))

 		return -1;

 	path = razor_path_from_parsed_uri(&ru, &tmp_error);

 	if (razor_error_matches(tmp_error, RAZOR_GENERAL_ERROR,

 	    RAZOR_GENERAL_ERROR_UNSUPPORTED_URI))

 		razor_error_free(tmp_error);

 	else if (!path) {

 		razor_propagate_error(error, tmp_error, NULL);

 		razor_uri_destroy(&ru);

 		return -1;

 	}

 	if (path) {

 		razor_uri_destroy(&ru);

 		retval = razor_file_unlink(path, error);

 		free(path);

 	} else {

 		entry = razor_uri_get_vtable_entry(ru.scheme);

 		razor_uri_destroy(&ru);

 		if (!entry || !entry->vtable.unlink) {

 			retval = -1;

 			razor_set_error(error, RAZOR_GENERAL_ERROR,

 					RAZOR_GENERAL_ERROR_UNSUPPORTED_URI,

 					uri, "No URI handler installed");

 		} else

 			retval = entry->vtable.unlink(uri, error);

 	}

 	return retval;

 }

 int razor_uri_open(const char *uri, int flags, mode_t mode,

 		   struct razor_error **error)

 {

 	int retval;

 	char *path;

 	struct razor_uri ru;

 	struct razor_uri_vtable_entry *entry;

 	struct razor_error *tmp_error = NULL;

 	if (razor_uri_parse(&ru, uri, error))

 		return -1;

 	path = razor_path_from_parsed_uri(&ru, &tmp_error);

 	if (razor_error_matches(tmp_error, RAZOR_GENERAL_ERROR,

 	    RAZOR_GENERAL_ERROR_UNSUPPORTED_URI))

 		razor_error_free(tmp_error);

 	else if (!path) {

 		razor_propagate_error(error, tmp_error, NULL);

 		razor_uri_destroy(&ru);

 		return -1;

 	}

 	if (path) {

 		razor_uri_destroy(&ru);

 		retval = razor_file_open(path, flags, mode, error);

 		free(path);

 	} else {

 		entry = razor_uri_get_vtable_entry(ru.scheme);

 		razor_uri_destroy(&ru);

 		if (!entry || !entry->vtable.open) {

 			retval = -1;

 			razor_set_error(error, RAZOR_GENERAL_ERROR,

 					RAZOR_GENERAL_ERROR_UNSUPPORTED_URI,

 					uri, "No URI handler installed");

 		} else

 			retval = entry->vtable.open(uri, flags, mode, error);

 	}

 	return retval;

 }

 int razor_uri_move(const char *src_uri, const char *dst_uri,

 		   struct razor_error **error)

 {

 	int retval;

 	char *src_path, *dst_path;

 	struct razor_uri src_ru, dst_ru;

 	struct razor_uri_vtable_entry *entry;

 	struct razor_error *tmp_error = NULL;

 	if (razor_uri_parse(&src_ru, src_uri, error) ||

 	    razor_uri_parse(&dst_ru, dst_uri, error))

 		return -1;

 	src_path = razor_path_from_parsed_uri(&src_ru, &tmp_error);

 	if (razor_error_matches(tmp_error, RAZOR_GENERAL_ERROR,

 	    RAZOR_GENERAL_ERROR_UNSUPPORTED_URI))

 		razor_error_free(tmp_error);

 	else if (!src_path) {

 		razor_propagate_error(error, tmp_error, NULL);

 		razor_uri_destroy(&src_ru);

 		return -1;

 	}

 	dst_path = razor_path_from_parsed_uri(&dst_ru, &tmp_error);

 	if (razor_error_matches(tmp_error, RAZOR_GENERAL_ERROR,

 	    RAZOR_GENERAL_ERROR_UNSUPPORTED_URI))

 		razor_error_free(tmp_error);

 	else if (!dst_path) {

 		razor_propagate_error(error, tmp_error, NULL);

 		razor_uri_destroy(&dst_ru);

 		razor_uri_destroy(&src_ru);

 		free(src_path);

 		return -1;

 	}

 	if (src_path && dst_path)

 		retval = razor_file_move(src_path, dst_path, error);

 	else {

 		if (!strcmp(src_ru.scheme, dst_ru.scheme))

 			entry = razor_uri_get_vtable_entry(src_ru.scheme);

 		else

 			entry = NULL;

 		if (entry && entry->vtable.move)

 			retval = entry->vtable.move(src_uri, dst_uri, error);

 		else if (strcmp(src_ru.scheme, dst_ru.scheme)) {

 			retval = -1;

 			razor_set_error(error, RAZOR_GENERAL_ERROR,

 					RAZOR_GENERAL_ERROR_UNSUPPORTED_URI,

 					dst_uri, "Cross-scheme URI move");

 		} else {

 			retval = -1;

 			razor_set_error(error, RAZOR_GENERAL_ERROR,

 					RAZOR_GENERAL_ERROR_UNSUPPORTED_URI,

 					src_path ? dst_uri : src_uri,

 					"No URI handler installed");

 		}

 	}

 	razor_uri_destroy(&src_ru);

 	razor_uri_destroy(&dst_ru);

 	free(src_path);

 	free(dst_path);

 	return retval;

 }

 void *razor_uri_get_contents(const char *uri, size_t *length, int private,

 			     struct razor_error **error)

 {

 	void *retval;

 	char *path;

 	struct razor_uri ru;

 	struct razor_uri_vtable_entry *entry;

 	struct razor_error *tmp_error = NULL;

 	if (razor_uri_parse(&ru, uri, error))

 		return NULL;

 	path = razor_path_from_parsed_uri(&ru, &tmp_error);

 	if (razor_error_matches(tmp_error, RAZOR_GENERAL_ERROR,

 	    RAZOR_GENERAL_ERROR_UNSUPPORTED_URI))

 		razor_error_free(tmp_error);

 	else if (!path) {

 		razor_propagate_error(error, tmp_error, NULL);

 		razor_uri_destroy(&ru);

 		return NULL;

 	}

 	if (path) {

 		razor_uri_destroy(&ru);

 		retval = razor_file_get_contents(path, length, private, error);

 		free(path);

 	} else {

 		entry = razor_uri_get_vtable_entry(ru.scheme);

 		razor_uri_destroy(&ru);

 		if (!entry || !entry->vtable.get_contents) {

 			retval = NULL;

 			razor_set_error(error, RAZOR_GENERAL_ERROR,

 					RAZOR_GENERAL_ERROR_UNSUPPORTED_URI,

 					uri, "No URI handler installed");

 		} else {

 			retval = entry->vtable.get_contents(uri, length,

 							    private, error);

 			if (retval)

 				ptr_array_add(&entry->open_files, retval);

 		}

 	}

 	return retval;

 }

 int razor_uri_free_contents(void *addr, size_t length)

 {

 	int retval, of;

 	struct razor_uri_vtable_entry *entry, *eend;

 	if (!addr)

 		return 0;

 	retval = razor_file_free_contents(addr, length);

 	if (retval != -2)

 		return retval;

 	eend = razor_uri_vtable_entries.data + razor_uri_vtable_entries.size;

 	for (entry = razor_uri_vtable_entries.data; entry < eend; entry++) {

 		of = ptr_array_find(&entry->open_files, addr);

 		if (of >= 0) {

 			if (entry->vtable.free_contents)

 				retval = entry->vtable.free_contents(addr,

 								     length);

 			ptr_array_remove_index(&entry->open_files, of);

 			break;

 		}

 	}

 	return retval;

 }

 int razor_uri_is_directory(const char *uri, struct razor_error **error)

 {

 	int retval;

 	char *path;

 	struct razor_uri ru;

 	struct razor_uri_vtable_entry *entry;

 	struct razor_error *tmp_error = NULL;

 	if (razor_uri_parse(&ru, uri, error))

 		return -1;

 	path = razor_path_from_parsed_uri(&ru, &tmp_error);

 	if (razor_error_matches(tmp_error, RAZOR_GENERAL_ERROR,

 	    RAZOR_GENERAL_ERROR_UNSUPPORTED_URI))

 		razor_error_free(tmp_error);

 	else if (!path) {

 		razor_propagate_error(error, tmp_error, NULL);

 		razor_uri_destroy(&ru);

 		return -1;

 	}

 	if (path) {

 		razor_uri_destroy(&ru);

 		retval = razor_file_is_directory(path, error);

 		free(path);

 	} else {

 		entry = razor_uri_get_vtable_entry(ru.scheme);

 		razor_uri_destroy(&ru);

 		if (!entry || !entry->vtable.is_directory) {

 			retval = -1;

 			razor_set_error(error, RAZOR_GENERAL_ERROR,

 					RAZOR_GENERAL_ERROR_UNSUPPORTED_URI,

 					uri, "No URI handler installed");

 		} else

 			retval = entry->vtable.is_directory(uri, error);

 	}

 	return retval;

 }

 char *razor_uri_mkdtemp_near(const char *uri, const char *template,

 			     struct razor_error **error)

 {

 	char *retval, *s;

 	char *path;

 	struct razor_uri ru;

 	struct razor_uri_vtable_entry *entry;

 	struct razor_error *tmp_error = NULL;

 	if (razor_uri_parse(&ru, uri, error))

 		return NULL;

 	path = razor_path_from_parsed_uri(&ru, &tmp_error);

 	if (razor_error_matches(tmp_error, RAZOR_GENERAL_ERROR,

 	    RAZOR_GENERAL_ERROR_UNSUPPORTED_URI))

 		razor_error_free(tmp_error);

 	else if (!path) {

 		razor_propagate_error(error, tmp_error, NULL);

 		razor_uri_destroy(&ru);

 		return NULL;

 	}

 	if (path) {

 		razor_uri_destroy(&ru);

 		s = razor_file_mkdtemp_near(path, template, error);

 		retval = razor_path_to_uri(s);

 		free(s);

 		free(path);

 	} else {

 		entry = razor_uri_get_vtable_entry(ru.scheme);

 		razor_uri_destroy(&ru);

 		if (!entry || !entry->vtable.mkdtemp_near) {

 			retval = NULL;

 			razor_set_error(error, RAZOR_GENERAL_ERROR,

 					RAZOR_GENERAL_ERROR_UNSUPPORTED_URI,

 					uri, "No URI handler installed");

 		} else

 			retval = entry->vtable.mkdtemp_near(uri, template,

 							    error);

 	}

 	return retval;

 }

 void *razor_uri_opendir(const char *uri, struct razor_error **error)

 {

 	void *retval;

 	char *path;

 	struct razor_uri ru;

 	struct razor_uri_vtable_entry *entry;

 	struct razor_error *tmp_error = NULL;

 	if (razor_uri_parse(&ru, uri, error))

 		return NULL;

 	path = razor_path_from_parsed_uri(&ru, &tmp_error);

 	if (razor_error_matches(tmp_error, RAZOR_GENERAL_ERROR,

 	    RAZOR_GENERAL_ERROR_UNSUPPORTED_URI))

 		razor_error_free(tmp_error);

 	else if (!path) {

 		razor_propagate_error(error, tmp_error, NULL);

 		razor_uri_destroy(&ru);

 		return NULL;

 	}

 	if (path) {

 		razor_uri_destroy(&ru);

 		retval = razor_file_opendir(path, error);

 		free(path);

 	} else {

 		entry = razor_uri_get_vtable_entry(ru.scheme);

 		razor_uri_destroy(&ru);

 		if (!entry || !entry->vtable.opendir) {

 			retval = NULL;

 			razor_set_error(error, RAZOR_GENERAL_ERROR,

 					RAZOR_GENERAL_ERROR_UNSUPPORTED_URI,

 					uri, "No URI handler installed");

 		} else {

 			retval = entry->vtable.opendir(uri, error);

 			if (retval)

 				ptr_array_add(&entry->open_directories, retval);

 		}

 	}

 	return retval;

 }

 char *razor_uri_readdir(void *dir, struct razor_error **error)

 {

 	int od;

 	char *retval;

 	struct razor_uri_vtable_entry *entry, *eend;

 	retval = razor_file_readdir(dir, error);

 	if (retval != (char *)-1)

 		return retval;

 	eend = razor_uri_vtable_entries.data + razor_uri_vtable_entries.size;

 	for (entry = razor_uri_vtable_entries.data; entry < eend; entry++) {

 		od = ptr_array_find(&entry->open_directories, dir);

 		if (od >= 0) {

 			if (entry->vtable.readdir)

 				retval = entry->vtable.readdir(dir, error);

 			break;

 		}

 	}

 	if (retval == (char *)-1) {

 		retval = NULL;

 		razor_set_error(error, RAZOR_GENERAL_ERROR,

 				RAZOR_GENERAL_ERROR_FAILED, NULL,

 				"Invalid directory handle");

 	}

 	return retval;

 }

 int razor_uri_closedir(void *dir, struct razor_error **error)

 {

 	int od;

 	int retval;

 	struct razor_uri_vtable_entry *entry, *eend;

 	retval = razor_file_closedir(dir, error);

 	if (retval != -2)

 		return retval;

 	eend = razor_uri_vtable_entries.data + razor_uri_vtable_entries.size;

 	for (entry = razor_uri_vtable_entries.data; entry < eend; entry++) {

 		od = ptr_array_find(&entry->open_directories, dir);

 		if (od >= 0) {

 			if (entry->vtable.closedir)

 				retval = entry->vtable.closedir(dir, error);

 			break;

 		}

 	}

 	if (retval == -2)

 		razor_set_error(error, RAZOR_GENERAL_ERROR,

 				RAZOR_GENERAL_ERROR_FAILED, NULL,

 				"Invalid directory handle");

 	return retval;

 }

 RAZOR_EXPORT int razor_uri_set_vtable(const char *scheme,

   struct razor_uri_vtable *vtable, struct razor_error **error)

 {

 	struct razor_uri_vtable_entry *entry, *eend;

 	if (!strcmp0(scheme, "file")) {

 		/*

 		 * There's no fundamental reason why we couldn't support

 		 * this, but it's a lot of work without any obvious need.

 		 */

 		razor_set_error(error, RAZOR_GENERAL_ERROR,

 				RAZOR_GENERAL_ERROR_FAILED, scheme,

 				"Can't override file scheme handler");

 		return -1;

 	}

 	if (vtable->structure_size < sizeof(struct razor_uri_vtable)) {

 		/*

 		 * A future version of the API might add vfuncs to the

 		 * table (which we ignore), but won't remove any.

 		 */

 		razor_set_error(error, RAZOR_GENERAL_ERROR,

 				RAZOR_GENERAL_ERROR_FAILED, scheme,

 				"Invalid vtable structure size");

 		return -1;

 	}

 	eend = razor_uri_vtable_entries.data + razor_uri_vtable_entries.size;

 	for (entry = razor_uri_vtable_entries.data; entry < eend; entry++) {

 		if (!strcmp0(entry->scheme, scheme))

 			break;

 	}

 	if (entry == eend) {

 		if (!vtable)

 			return 0;

 		entry = array_add(&razor_uri_vtable_entries, sizeof *entry);

 		entry->scheme = scheme ? strdup(scheme) : NULL;

 		array_init(&entry->open_files);

 		array_init(&entry->open_directories);

 	} else if (entry->open_files.size || entry->open_directories.size) {

 		razor_set_error(error, RAZOR_GENERAL_ERROR,

 				RAZOR_GENERAL_ERROR_FAILED, scheme,

 				"URI handler busy");

 		return -1;

 	}

 	if (vtable) {

 		entry->vtable = *vtable;

 		entry->vtable.structure_size = sizeof(struct razor_uri_vtable);

 	} else {

 		free(entry->scheme);

 		if (entry + 1 < eend)

 			memmove(entry, entry + 1, eend - (entry + 1));

 		array_set_size(&razor_uri_vtable_entries,

 			       razor_uri_vtable_entries.size - sizeof *entry);

 	}

 	return 0;

 }