/*

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

  * Copyright (C) 2008  Red Hat, Inc

  * Copyright (C) 2009  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>

 #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 "razor-internal.h"

 #ifndef O_BINARY

 #define O_BINARY	0

 #endif

 #define RAZOR_ASCII_ISALPHA(c)	\

 			((c) >= 'A' && (c) <= 'Z' || (c) >= 'a' && (c) <= 'z')

 /* Required by gnulib on non-libc platforms */

 char *program_name = "librazor";

 static int allow_all_root_names = 0;

 /*

  * Primarily intended for testing named roots under UNIX platforms.

  */

 RAZOR_EXPORT void razor_disable_root_name_checks(int disable)

 {

 	allow_all_root_names = disable;

 }

 static int razor_valid_root_name(const char *name)

 {

 	if (allow_all_root_names)

 		return !strchr(name,'/');

 #ifdef MSWIN_API

 	return RAZOR_ASCII_ISALPHA(name[0]) && name[1] == ':' &&

 	       name[2] == '\0';

 #else

 	return name[0] == '\0';

 #endif

 }

 int

 razor_create_dir(const char *root, const char *path)

 {

 	char buffer[PATH_MAX], *p;

 	const char *slash, *next;

 	struct stat buf;

 	/* Create all sub-directories in dir. We know root exists and

 	 * is a dir, root does not end in a '/', and path either has a

 	 * leading '/' or (on MS-Windows only) root is the empty string

 	 * and path starts with drive (eg., "c:/windows"). */

 	strcpy(buffer, root);

 	p = buffer + strlen(buffer);

 	slash = path;

 	for (slash = path; *slash != '\0'; slash = next) {

 		next = strchr(slash + 1, '/');

 		if (next == NULL)

 			break;

 		memcpy(p, slash, next - slash);

 		p += next - slash;

 		*p = '\0';

 		if (razor_valid_root_name(buffer))

 			continue;

 		if (stat(buffer, &buf) == 0) {

 			if (!S_ISDIR(buf.st_mode)) {

 				fprintf(stderr,

 					"%s exists but is not a directory\n",

 					buffer);

 				return -1;

 			}

 		} else if (mkdir(buffer, 0777) < 0) {

 			fprintf(stderr, "failed to make directory %s: %s\n",

 				buffer, strerror(errno));

 			return -1;

 		}

 		/* FIXME: What to do about permissions for dirs we

 		 * have to create but are not in the cpio archive? */

 	}

 	return 0;

 }

 int

 razor_remove(const char *path)

 {

 #ifdef MSWIN_API

 	DWORD err;

 	if (DeleteFile(path))

 		return 0;

 	err = GetLastError();

 	if (err == ERROR_FILE_NOT_FOUND || err == ERROR_PATH_NOT_FOUND)

 		return 0;

 	if (SetFileAttributes(path, FILE_ATTRIBUTE_NORMAL) && DeleteFile(path))

 		return 0;

 	if (RemoveDirectory(path) || GetLastError() == ERROR_DIR_NOT_EMPTY)

 		return 0;

 	/*

 	 * It would be tempting to use:

 	 * 	MoveFileEx(path, NULL, MOVEFILE_DELAY_UNTIL_REBOOT)

 	 * but unless we can guarantee that the system will be rebooted

 	 * before we (or some other application) write another file with the

 	 * same path, this is likely to cause more problems than it solves.

 	 */

 	/* Use remove() as a fallback so that errno is set appropriately */

 #endif

 	return remove(path);

 }

 int

 razor_write(int fd, const void *data, size_t size)

 {

 	size_t rest;

 	ssize_t written;

 	const unsigned char *p;

 	rest = size;

 	p = data;

 	while (rest > 0) {

 		written = write(fd, p, rest);

 		if (written < 0) {

 			perror("write error");

 			return -1;

 		}

 		rest -= written;

 		p += written;

 	}

 	return 0;

 }

 void *

 razor_file_get_contents(const char *filename, size_t *length)

 {

 	int fd;

 	struct stat st;

 	void *addr;

 #if !HAVE_SYS_MMAN_H

 	size_t nb;

 	ssize_t res;

 #endif

 	fd = open(filename, O_RDONLY | O_BINARY);

 	if (fd < 0)

 		return NULL;

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

 		close(fd);

 		return NULL;

 	}

 	*length = st.st_size;

 #if HAVE_SYS_MMAN_H

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

 #else

 	addr = malloc(st.st_size);

 	if (addr) {

 		nb = 0;

 		while(nb < st.st_size) {

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

 			if (res <= 0) {

 				free(addr);

 				addr = NULL;

 				break;

 			}

 			nb += res;

 		}

 	}

 #endif

 	close(fd);

 #if HAVE_SYS_MMAN_H

 	if (addr == MAP_FAILED)

 		addr = NULL;

 #endif

 	return addr;

 }

 int

 razor_file_free_contents(void *addr, size_t length)

 {

 #if HAVE_SYS_MMAN_H

 	return munmap(addr, length);

 #else

 	free(addr);

 	return 0;

 #endif

 }

 struct qsort_context {

 	size_t size;

 	razor_compare_with_data_func_t compare;

 	void *data;

 };

 static void

 qsort_swap(void *p1, void *p2, size_t size)

 {

 	char buffer[size];

 	memcpy(buffer, p1, size);

 	memcpy(p1, p2, size);

 	memcpy(p2, buffer, size);

 }

 static void

 __qsort_with_data(void *base, size_t nelem, uint32_t *map,

 		  struct qsort_context *ctx)

 {

 	void *p, *start, *end, *pivot;

 	uint32_t *mp, *mstart, *mend, tmp;

 	int left, right, result;

 	size_t size = ctx->size;

 	p = base;

 	start = base;

 	end = base + nelem * size;

 	mp = map;

 	mstart = map;

 	mend = map + nelem;

 	pivot = base + (rand() % nelem) * size;

 	while (p < end) {

 		result = ctx->compare(p, pivot, ctx->data);

 		if (result < 0) {

 			qsort_swap(p, start, size);

 			tmp = *mp;

 			*mp = *mstart;

 			*mstart = tmp;

 			if (start == pivot)

 				pivot = p;

 			start += size;

 			mstart++;

 			p += size;

 			mp++;

 		} else if (result == 0) {

 			p += size;

 			mp++;

 		} else {

  			end -= size;

 			mend--;

 			qsort_swap(p, end, size);

 			tmp = *mp;

 			*mp = *mend;

 			*mend = tmp;

 			if (end == pivot)

 				pivot = p;

 		}

 	}

 	left = (start - base) / size;

 	right = (base + nelem * size - end) / size;

 	if (left > 1)

 		__qsort_with_data(base, left, map, ctx);

 	if (right > 1)

 		__qsort_with_data(end, right, mend, ctx);

 }

 uint32_t *

 razor_qsort_with_data(void *base, size_t nelem, size_t size,

 		      razor_compare_with_data_func_t compare, void *data)

 {

 	struct qsort_context ctx;

 	uint32_t *map;

 	int i;

 	if (nelem == 0)

 		return NULL;

 	ctx.size = size;

 	ctx.compare = compare;

 	ctx.data = data;

 	map = malloc(nelem * sizeof (uint32_t));

 	for (i = 0; i < nelem; i++)

 		map[i] = i;

 	__qsort_with_data(base, nelem, map, &ctx);

 	return map;

 }

 void environment_init(struct environment *env)

 {

 	env->is_set = 0;

 	array_init(&env->string_pool);

 	array_init(&env->vars);

 }

 void environment_add_variable(struct environment *env,

 			      const char *variable, const char *value)

 {

 	char *s;

 	uint32_t *r;

 	assert(!env->is_set);

 	s = array_add(&env->string_pool,

 		      strlen(variable) + strlen(value) + 2);

 	sprintf(s, "%s=%s", variable, value);

 	r = array_add(&env->vars, sizeof *r);

 	*r = s - (char *)env->string_pool.data;

 }

 void environment_set(struct environment *env)

 {

 	int i, count;

 	char *s;

         uint32_t *r;

 	if (!env->is_set) {

 		count = env->vars.size / sizeof(uint32_t);

 		r = (uint32_t *)env->vars.data;

 		for (i = 0; i < count; i++) {

 			s = env->string_pool.data + *r++;

 			putenv(s);

 		}

 		env->is_set = 1;

 	}

 }

 void environment_unset(struct environment *env)

 {

 	int i, count;

 	char c, *s, *t;

         uint32_t *r;

 	if (env->is_set) {

 		count = env->vars.size / sizeof(uint32_t);

 		r = (uint32_t *)env->vars.data;

 		for (i = 0; i < count; i++) {

 			s = env->string_pool.data + *r++;

 			t = strchr(s, '=') + 1;

 			c = *t;

 			*t = '\0';

 			putenv(s);

 			*t = c;

 		}

 		env->is_set = 0;

 	}

 }

 void environment_release(struct environment *env)

 {

 	environment_unset(env);

 	array_release(&env->string_pool);

 	array_release(&env->vars);

 }