#include "config.h"
#include <stdlib.h>
#include <string.h>

#ifndef HAVE_SETENV
int setenv(const char *key, const char *value, int overwrite) {
	char *line;

	if ((key != NULL) && (value != NULL)) {
		if ((getenv(key) == NULL) || overwrite) {
			if ((line = (char*)malloc(strlen(key) + strlen(value) + 2)) != NULL) {
				sprintf(line, "%s=%s", key, value);
				return putenv(line);
			} else {
				return -1;
			}
		}

		return 0;
	}

	return -1;
}
#endif

#ifndef HAVE_UNSETENV
int unsetenv(char *key) {
	if (key != NULL) {
		return putenv(key);
	}

	return -1;
}
#endif

#ifndef HAVE_CLEARENV
void clearenv(void) {
	extern char **environ;
	char *eq, key[256];
	int len;

	while (*environ != NULL) {
		if ((eq = strchr(*environ, '=')) != NULL) {
			if ((len = eq - *environ) < 256) {
				memcpy(key, *environ, len);
				key[len] = '\0';
				unsetenv(key);
			}
		}
		environ++;
	}
}
#endif

#ifndef HAVE_STRCASECMP
int strcasecmp(char *str1, char *str2) {
	char c1, c2;

	if ((str1 != NULL) && (str2 != NULL)) {
		while (*str1 != '\0') {
			if (*str1 != *str2) {
				c1 = *str1;
				if ((c1 >= 'A') && (c1 <= 'Z')) {
					c1 += 32;
				}
				c2 = *str2;
				if ((c2 >= 'A') && (c2 <= 'Z')) {
					c2 += 32;
				}
				if (c1 != c2) {
					return -1;
				}
			}
			str1++;
			str2++;
		}

		if (*str2 == '\0') {
			return 0;
		}
	}

	return -1;
}
#endif

#ifndef HAVE_STRNCASECMP
int strncasecmp(char *str1, char *str2, int len) {
	char c1, c2;

	if ((str1 == NULL) || (str2 == NULL)) {
		return -1;
	}

	while (len-- > 0) {
		if (*str1 != *str2) {
			c1 = *str1;
			if ((c1 >= 'A') && (c1 <= 'Z')) {
				c1 += 32;
			}
			c2 = *str2;
			if ((c2 >= 'A') && (c2 <= 'Z')) {
				c2 += 32;
			}
			if (c1 != c2) {
				return -1;
			}
		}
		if (*str1 == '\0') {
			break;
		}
		str1++;
		str2++;
	}

	return 0;
}
#endif

#ifndef HAVE_STRCASESTR
char *strcasestr(char *haystack, char *needle) {
	int i, len, steps;

	if ((haystack != NULL) && (needle != NULL)) {
		len = strlen(needle);
		steps = strlen(haystack) - len + 1;
		for (i = 0; i < steps; i++) {
			if (strncasecmp(haystack + i, needle, len) == 0) {
				return haystack + i;
			}
		}
	}

	return NULL;
}
#endif