/*
	usbmuxd - iPhone/iPod Touch USB multiplex server daemon

Copyright (C) 2009	Hector Martin "marcan" <hector@marcansoft.com>
Copyright (C) 2009	Nikias Bassen <nikias@gmx.li>
Copyright (c) 2013	Federico Mena Quintero

This library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation, either version 2.1 of the
License, or (at your option) any later version.

This library 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 Lesser 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

*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <stdarg.h>
#include <sys/time.h>

#include "utils.h"

#include "log.h"
#define util_error(...) usbmuxd_log(LL_ERROR, __VA_ARGS__)

void fdlist_create(struct fdlist *list)
{
	list->count = 0;
	list->capacity = 4;
	list->owners = malloc(sizeof(*list->owners) * list->capacity);
	list->fds = malloc(sizeof(*list->fds) * list->capacity);
}
void fdlist_add(struct fdlist *list, enum fdowner owner, int fd, short events)
{
	if(list->count == list->capacity) {
		list->capacity *= 2;
		list->owners = realloc(list->owners, sizeof(*list->owners) * list->capacity);
		list->fds = realloc(list->fds, sizeof(*list->fds) * list->capacity);
	}
	list->owners[list->count] = owner;
	list->fds[list->count].fd = fd;
	list->fds[list->count].events = events;
	list->fds[list->count].revents = 0;
	list->count++;
}

void fdlist_free(struct fdlist *list)
{
	list->count = 0;
	list->capacity = 0;
	free(list->owners);
	list->owners = NULL;
	free(list->fds);
	list->fds = NULL;
}

void fdlist_reset(struct fdlist *list)
{
	list->count = 0;
}

#define CAPACITY_STEP 8

void collection_init(struct collection *col)
{
	col->list = malloc(sizeof(void *) * CAPACITY_STEP);
	memset(col->list, 0, sizeof(void *) * CAPACITY_STEP);
	col->capacity = CAPACITY_STEP;
}

void collection_free(struct collection *col)
{
	free(col->list);
	col->list = NULL;
	col->capacity = 0;
}

void collection_add(struct collection *col, void *element)
{
	int i;
	for(i=0; i<col->capacity; i++) {
		if(!col->list[i]) {
			col->list[i] = element;
			return;
		}
	}
	col->list = realloc(col->list, sizeof(void*) * (col->capacity + CAPACITY_STEP));
	memset(&col->list[col->capacity], 0, sizeof(void *) * CAPACITY_STEP);
	col->list[col->capacity] = element;
	col->capacity += CAPACITY_STEP;
}

void collection_remove(struct collection *col, void *element)
{
	int i;
	for(i=0; i<col->capacity; i++) {
		if(col->list[i] == element) {
			col->list[i] = NULL;
			return;
		}
	}
	util_error("collection_remove: element %p not present in collection %p (cap %d)", element, col, col->capacity);
}

int collection_count(struct collection *col)
{
	int i, cnt = 0;
	for(i=0; i<col->capacity; i++) {
		if(col->list[i])
			cnt++;
	}
	return cnt;
}

void collection_copy(struct collection *dest, struct collection *src)
{
	if (!dest || !src) return;
	dest->capacity = src->capacity;
	dest->list = malloc(sizeof(void*) * src->capacity);
	memcpy(dest->list, src->list, sizeof(void*) * src->capacity);
}

#ifndef HAVE_STPCPY
/**
 * Copy characters from one string into another
 *
 * @note: The strings should not overlap, as the behavior is undefined.
 *
 * @s1: The source string.
 * @s2: The destination string.
 *
 * @return a pointer to the terminating `\0' character of @s1,
 * or NULL if @s1 or @s2 is NULL.
 */
char *stpcpy(char * s1, const char * s2)
{
	if (s1 == NULL || s2 == NULL)
		return NULL;

	strcpy(s1, s2);

	return s1 + strlen(s2);
}
#endif

/**
 * Concatenate strings into a newly allocated string
 *
 * @note: Specify NULL for the last string in the varargs list
 *
 * @str: The first string in the list
 * @...: Subsequent strings.  Use NULL for the last item.
 *
 * @return a newly allocated string, or NULL if @str is NULL.  This will also
 * return NULL and set errno to ENOMEM if memory is exhausted.
 */
char *string_concat(const char *str, ...)
{
	size_t len;
	va_list args;
	char *s;
	char *result;
	char *dest;

	if (!str)
		return NULL;

	/* Compute final length */

	len = strlen(str) + 1; /* plus 1 for the null terminator */

	va_start(args, str);
	s = va_arg(args, char *);
	while (s) {
		len += strlen(s);
		s = va_arg(args, char*);
	}
	va_end(args);

	/* Concat each string */

	result = malloc(len);
	if (!result)
		return NULL; /* errno remains set */

	dest = result;

	dest = stpcpy(dest, str);

	va_start(args, str);
	s = va_arg(args, char *);
	while (s) {
		dest = stpcpy(dest, s);
		s = va_arg(args, char *);
	}
	va_end(args);

	return result;
}

void buffer_read_from_filename(const char *filename, char **buffer, uint64_t *length)
{
	FILE *f;
	uint64_t size;

	*length = 0;

	f = fopen(filename, "rb");
	if (!f) {
		return;
	}

	fseek(f, 0, SEEK_END);
	size = ftell(f);
	rewind(f);

	if (size == 0) {
		fclose(f);
		return;
	}

	*buffer = (char*)malloc(sizeof(char)*(size+1));
	if (fread(*buffer, sizeof(char), size, f) != size) {
		usbmuxd_log(LL_ERROR, "%s: ERROR: couldn't read %d bytes from %s", __func__, (int)size, filename);
	}
	fclose(f);

	*length = size;
}

void buffer_write_to_filename(const char *filename, const char *buffer, uint64_t length)
{
	FILE *f;

	f = fopen(filename, "wb");
	if (f) {
		fwrite(buffer, sizeof(char), length, f);
		fclose(f);
	}
}

int plist_read_from_filename(plist_t *plist, const char *filename)
{
	char *buffer = NULL;
	uint64_t length;

	if (!filename)
		return 0;

	buffer_read_from_filename(filename, &buffer, &length);

	if (!buffer) {
		return 0;
	}

	if ((length > 8) && (memcmp(buffer, "bplist00", 8) == 0)) {
		plist_from_bin(buffer, length, plist);
	} else {
		plist_from_xml(buffer, length, plist);
	}

	free(buffer);

	return 1;
}

int plist_write_to_filename(plist_t plist, const char *filename, enum plist_format_t format)
{
	char *buffer = NULL;
	uint32_t length;

	if (!plist || !filename)
		return 0;

	if (format == PLIST_FORMAT_XML)
		plist_to_xml(plist, &buffer, &length);
	else if (format == PLIST_FORMAT_BINARY)
		plist_to_bin(plist, &buffer, &length);
	else
		return 0;

	buffer_write_to_filename(filename, buffer, length);

	free(buffer);

	return 1;
}

/**
 * Get number of milliseconds since the epoch.
 */
uint64_t mstime64(void)
{
	struct timeval tv;
	gettimeofday(&tv, NULL);

  // Careful, avoid overflow on 32 bit systems
  // time_t could be 4 bytes
	return ((long long)tv.tv_sec) * 1000LL + ((long long)tv.tv_usec) / 1000LL;
}