/*

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

 * Copyright (C) 2008  Red Hat, Inc

 * Copyright (C) 2009, 2011, 2012, 2014  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>

#else

#include <sys/utsname.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

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

char *program_name = "librazor";

void *

zalloc(size_t size)

{

	void *p;

	p = malloc(size);

	memset(p, 0, size);

	return p;

}

#if HAVE_SYS_MMAN_H

#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, };

#endif	/* HAVE_SYS_MMAN_H */

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;

#if HAVE_SYS_MMAN_H

	struct open_file *of, *ofend;

#endif

	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;

#if HAVE_SYS_MMAN_H

	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 (!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) {

#if HAVE_SYS_MMAN_H

			of->flags = OPEN_FILE_USED;

#endif

			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);

#if HAVE_SYS_MMAN_H

	of->addr = addr;

	of->length = st.st_size;

#endif

	return addr;

}

int razor_file_free_contents(void *addr, size_t length)

{

#if HAVE_SYS_MMAN_H

	int retval, mmapped;

	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 1;

	length = of->length;

	mmapped = of->flags & OPEN_FILE_MMAPPED;

	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 (mmapped)

		return munmap(addr, length);

#endif

	free(addr);

	return 0;

}

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];

	if (p1 != p2) {

		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;

#ifndef WIN32

	char *t;

#endif

        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++;

#ifdef WIN32

			putenv(s);

#else

			t = strchr(s, '=');

			*t = '\0';

			setenv(s, t + 1, 1);

			*t = '=';

#endif

		}

		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, '=');

#ifdef WIN32

			t++;

			c = *t;

			*t = '\0';

			putenv(s);

			*t = c;

#else

			c = *t;

			*t = '\0';

			unsetenv(s);

			*t = c;

#endif

		}

		env->is_set = 0;

	}

}

void environment_release(struct environment *env)

{

	environment_unset(env);

	array_release(&env->string_pool);

	array_release(&env->vars);

}

RAZOR_EXPORT char *razor_concat(const char *s, ...)

{

	va_list args;

	const char *string;

	char *concat;

	size_t n, len;

	va_start(args, s);

	len = strlen(s);

	while((string = va_arg(args, const char *)))

		len += strlen(string);

	va_end(args);

	concat = malloc(len + 1);

	if (!concat)

		return NULL;

	va_start(args, s);

	len = strlen(s);

	memcpy(concat, s, len);

	n = len;

	while((string = va_arg(args, const char *))) {

		len = strlen(string);

		memcpy(concat + n, string, len);

		n += len;

	}

	va_end(args);

	concat[n] = '\0';

	return concat;

}

RAZOR_EXPORT const char *razor_system_arch(void)

{

#ifdef MSWIN_API

	SYSTEM_INFO si;

	GetNativeSystemInfo(&si);

	switch(si.wProcessorArchitecture)

	{

		case PROCESSOR_ARCHITECTURE_INTEL:

			return "i686";

		case PROCESSOR_ARCHITECTURE_AMD64:

			return "x86_64";

		default:

			return NULL;

	}

#else

	static struct utsname un;

	if (uname(&un))

		return NULL;

	else

		return un.machine;

#endif

}

#ifdef MSWIN_API

char *razor_utf16_to_utf8(const wchar_t *utf16, int len)

{

	int n;

	char *utf8;

	if (len == 0)

		return strdup("");

	n = WideCharToMultiByte(CP_UTF8, 0, utf16, len, NULL, 0, NULL, NULL);

	if (len > 0)

		n++;

	utf8 = malloc(n);

	(void)WideCharToMultiByte(CP_UTF8, 0, utf16, len, utf8, n, NULL, NULL);

	if (len > 0)

		utf8[n - 1] = 0;

	return utf8;

}

wchar_t *razor_utf8_to_utf16(const char *utf8, int len)

{

	int n;

	wchar_t *utf16;

	if (len == 0) {

		utf16 = calloc(1, sizeof(wchar_t));

		return utf16;

	}

	n = MultiByteToWideChar(CP_UTF8, 0, utf8, len, NULL, 0);

	if (len > 0)

		n++;

	utf16 = malloc(n * sizeof(wchar_t));

	(void)MultiByteToWideChar(CP_UTF8, 0, utf8, len, utf16, n);

	if (len > 0)

		utf16[n - 1] = 0;

	return utf16;

}

#endif	/* MSWIN_API */