text: /*
   * Copyright (C) the libgit2 contributors. All rights reserved.
   *
   * This file is part of libgit2, distributed under the GNU GPL v2 with
   * a Linking Exception. For full terms see the included COPYING file.
   */
  #include <git2.h>
  #include "common.h"
  #include <stdarg.h>
  #include <stdio.h>
  #include <ctype.h>
  #include "posix.h"
  #include "fileops.h"
  
  #ifdef _MSC_VER
  # include <Shlwapi.h>
  #endif
  
  void git_libgit2_version(int *major, int *minor, int *rev)
  {
  	*major = LIBGIT2_VER_MAJOR;
  	*minor = LIBGIT2_VER_MINOR;
  	*rev = LIBGIT2_VER_REVISION;
  }
  
  int git_libgit2_capabilities()
  {
  	return 0
  #ifdef GIT_THREADS
  		| GIT_CAP_THREADS
  #endif
  #if defined(GIT_SSL) || defined(GIT_WINHTTP)
  		| GIT_CAP_HTTPS
  #endif
  	;
  }
  
  /* Declarations for tuneable settings */
  extern size_t git_mwindow__window_size;
  extern size_t git_mwindow__mapped_limit;
  extern size_t git_odb__cache_size;
  
  static int config_level_to_futils_dir(int config_level)
  {
  	int val = -1;
  
  	switch (config_level) {
  	case GIT_CONFIG_LEVEL_SYSTEM: val = GIT_FUTILS_DIR_SYSTEM; break;
  	case GIT_CONFIG_LEVEL_XDG:    val = GIT_FUTILS_DIR_XDG; break;
  	case GIT_CONFIG_LEVEL_GLOBAL: val = GIT_FUTILS_DIR_GLOBAL; break;
  	default:
  		giterr_set(
  			GITERR_INVALID, "Invalid config path selector %d", config_level);
  	}
  
  	return val;
  }
  
  int git_libgit2_opts(int key, ...)
  {
  	int error = 0;
  	va_list ap;
  
  	va_start(ap, key);
  
  	switch (key) {
  	case GIT_OPT_SET_MWINDOW_SIZE:
  		git_mwindow__window_size = va_arg(ap, size_t);
  		break;
  
  	case GIT_OPT_GET_MWINDOW_SIZE:
  		*(va_arg(ap, size_t *)) = git_mwindow__window_size;
  		break;
  
  	case GIT_OPT_SET_MWINDOW_MAPPED_LIMIT:
  		git_mwindow__mapped_limit = va_arg(ap, size_t);
  		break;
  
  	case GIT_OPT_GET_MWINDOW_MAPPED_LIMIT:
  		*(va_arg(ap, size_t *)) = git_mwindow__mapped_limit;
  		break;
  
  	case GIT_OPT_GET_SEARCH_PATH:
  		if ((error = config_level_to_futils_dir(va_arg(ap, int))) >= 0) {
  			char *out = va_arg(ap, char *);
  			size_t outlen = va_arg(ap, size_t);
  
  			error = git_futils_dirs_get_str(out, outlen, error);
  		}
  		break;
  
  	case GIT_OPT_SET_SEARCH_PATH:
  		if ((error = config_level_to_futils_dir(va_arg(ap, int))) >= 0)
  			error = git_futils_dirs_set(error, va_arg(ap, const char *));
  		break;
  
  	case GIT_OPT_GET_ODB_CACHE_SIZE:
  		*(va_arg(ap, size_t *)) = git_odb__cache_size;
  		break;
  
  	case GIT_OPT_SET_ODB_CACHE_SIZE:
  		git_odb__cache_size = va_arg(ap, size_t);
  		break;
  	}
  
  	va_end(ap);
  
  	return error;
  }
  
  void git_strarray_free(git_strarray *array)
  {
  	size_t i;
  	for (i = 0; i < array->count; ++i)
  		git__free(array->strings[i]);
  
  	git__free(array->strings);
  
  	memset(array, 0, sizeof(*array));
  }
  
  int git_strarray_copy(git_strarray *tgt, const git_strarray *src)
  {
  	size_t i;
  
  	assert(tgt && src);
  
  	memset(tgt, 0, sizeof(*tgt));
  
  	if (!src->count)
  		return 0;
  
  	tgt->strings = git__calloc(src->count, sizeof(char *));
  	GITERR_CHECK_ALLOC(tgt->strings);
  
  	for (i = 0; i < src->count; ++i) {
  		if (!src->strings[i])
  			continue;
  
  		tgt->strings[tgt->count] = git__strdup(src->strings[i]);
  		if (!tgt->strings[tgt->count]) {
  			git_strarray_free(tgt);
  			memset(tgt, 0, sizeof(*tgt));
  			return -1;
  		}
  
  		tgt->count++;
  	}
  
  	return 0;
  }
  
  int git__strtol64(int64_t *result, const char *nptr, const char **endptr, int base)
  {
  	const char *p;
  	int64_t n, nn;
  	int c, ovfl, v, neg, ndig;
  
  	p = nptr;
  	neg = 0;
  	n = 0;
  	ndig = 0;
  	ovfl = 0;
  
  	/*
  	 * White space
  	 */
  	while (git__isspace(*p))
  		p++;
  
  	/*
  	 * Sign
  	 */
  	if (*p == '-' || *p == '+')
  		if (*p++ == '-')
  			neg = 1;
  
  	/*
  	 * Base
  	 */
  	if (base == 0) {
  		if (*p != '0')
  			base = 10;
  		else {
  			base = 8;
  			if (p[1] == 'x' || p[1] == 'X') {
  				p += 2;
  				base = 16;
  			}
  		}
  	} else if (base == 16 && *p == '0') {
  		if (p[1] == 'x' || p[1] == 'X')
  			p += 2;
  	} else if (base < 0 || 36 < base)
  		goto Return;
  
  	/*
  	 * Non-empty sequence of digits
  	 */
  	for (;; p++,ndig++) {
  		c = *p;
  		v = base;
  		if ('0'<=c && c<='9')
  			v = c - '0';
  		else if ('a'<=c && c<='z')
  			v = c - 'a' + 10;
  		else if ('A'<=c && c<='Z')
  			v = c - 'A' + 10;
  		if (v >= base)
  			break;
  		nn = n*base + v;
  		if (nn < n)
  			ovfl = 1;
  		n = nn;
  	}
  
  Return:
  	if (ndig == 0) {
  		giterr_set(GITERR_INVALID, "Failed to convert string to long. Not a number");
  		return -1;
  	}
  
  	if (endptr)
  		*endptr = p;
  
  	if (ovfl) {
  		giterr_set(GITERR_INVALID, "Failed to convert string to long. Overflow error");
  		return -1;
  	}
  
  	*result = neg ? -n : n;
  	return 0;
  }
  
  int git__strtol32(int32_t *result, const char *nptr, const char **endptr, int base)
  {
  	int error;
  	int32_t tmp_int;
  	int64_t tmp_long;
  
  	if ((error = git__strtol64(&tmp_long, nptr, endptr, base)) < 0)
  		return error;
  
  	tmp_int = tmp_long & 0xFFFFFFFF;
  	if (tmp_int != tmp_long) {
  		giterr_set(GITERR_INVALID, "Failed to convert. '%s' is too large", nptr);
  		return -1;
  	}
  
  	*result = tmp_int;
  
  	return error;
  }
  
  int git__strcmp(const char *a, const char *b)
  {
  	while (*a && *b && *a == *b)
  		++a, ++b;
  	return (int)(*(const unsigned char *)a) - (int)(*(const unsigned char *)b);
  }
  
  int git__strcasecmp(const char *a, const char *b)
  {
  	while (*a && *b && tolower(*a) == tolower(*b))
  		++a, ++b;
  	return (tolower(*a) - tolower(*b));
  }
  
  int git__strncmp(const char *a, const char *b, size_t sz)
  {
  	while (sz && *a && *b && *a == *b)
  		--sz, ++a, ++b;
  	if (!sz)
  		return 0;
  	return (int)(*(const unsigned char *)a) - (int)(*(const unsigned char *)b);
  }
  
  int git__strncasecmp(const char *a, const char *b, size_t sz)
  {
  	int al, bl;
  
  	do {
  		al = (unsigned char)tolower(*a);
  		bl = (unsigned char)tolower(*b);
  		++a, ++b;
  	} while (--sz && al && al == bl);
  
  	return al - bl;
  }
  
  void git__strntolower(char *str, size_t len)
  {
  	size_t i;
  
  	for (i = 0; i < len; ++i) {
  		str[i] = (char) tolower(str[i]);
  	}
  }
  
  void git__strtolower(char *str)
  {
  	git__strntolower(str, strlen(str));
  }
  
  int git__prefixcmp(const char *str, const char *prefix)
  {
  	for (;;) {
  		unsigned char p = *(prefix++), s;
  		if (!p)
  			return 0;
  		if ((s = *(str++)) != p)
  			return s - p;
  	}
  }
  
  int git__prefixcmp_icase(const char *str, const char *prefix)
  {
  	return strncasecmp(str, prefix, strlen(prefix));
  }
  
  int git__suffixcmp(const char *str, const char *suffix)
  {
  	size_t a = strlen(str);
  	size_t b = strlen(suffix);
  	if (a < b)
  		return -1;
  	return strcmp(str + (a - b), suffix);
  }
  
  char *git__strtok(char **end, const char *sep)
  {
  	char *ptr = *end;
  
  	while (*ptr && strchr(sep, *ptr))
  		++ptr;
  
  	if (*ptr) {
  		char *start = ptr;
  		*end = start + 1;
  
  		while (**end && !strchr(sep, **end))
  			++*end;
  
  		if (**end) {
  			**end = '\0';
  			++*end;
  		}
  
  		return start;
  	}
  
  	return NULL;
  }
  
  /* Similar to strtok, but does not collapse repeated tokens. */
  char *git__strsep(char **end, const char *sep)
  {
  	char *start = *end, *ptr = *end;
  
  	while (*ptr && !strchr(sep, *ptr))
  		++ptr;
  
  	if (*ptr) {
  		*end = ptr + 1;
  		*ptr = '\0';
  
  		return start;
  	}
  
  	return NULL;
  }
  
  void git__hexdump(const char *buffer, size_t len)
  {
  	static const size_t LINE_WIDTH = 16;
  
  	size_t line_count, last_line, i, j;
  	const char *line;
  
  	line_count = (len / LINE_WIDTH);
  	last_line = (len % LINE_WIDTH);
  
  	for (i = 0; i < line_count; ++i) {
  		line = buffer + (i * LINE_WIDTH);
  		for (j = 0; j < LINE_WIDTH; ++j, ++line)
  			printf("%02X ", (unsigned char)*line & 0xFF);
  
  		printf("| ");
  
  		line = buffer + (i * LINE_WIDTH);
  		for (j = 0; j < LINE_WIDTH; ++j, ++line)
  			printf("%c", (*line >= 32 && *line <= 126) ? *line : '.');
  
  		printf("\n");
  	}
  
  	if (last_line > 0) {
  
  		line = buffer + (line_count * LINE_WIDTH);
  		for (j = 0; j < last_line; ++j, ++line)
  			printf("%02X ", (unsigned char)*line & 0xFF);
  
  		for (j = 0; j < (LINE_WIDTH - last_line); ++j)
  			printf("	");
  
  		printf("| ");
  
  		line = buffer + (line_count * LINE_WIDTH);
  		for (j = 0; j < last_line; ++j, ++line)
  			printf("%c", (*line >= 32 && *line <= 126) ? *line : '.');
  
  		printf("\n");
  	}
  
  	printf("\n");
  }
  
  #ifdef GIT_LEGACY_HASH
  uint32_t git__hash(const void *key, int len, unsigned int seed)
  {
  	const uint32_t m = 0x5bd1e995;
  	const int r = 24;
  	uint32_t h = seed ^ len;
  
  	const unsigned char *data = (const unsigned char *)key;
  
  	while(len >= 4) {
  		uint32_t k = *(uint32_t *)data;
  
  		k *= m;
  		k ^= k >> r;
  		k *= m;
  
  		h *= m;
  		h ^= k;
  
  		data += 4;
  		len -= 4;
  	}
  
  	switch(len) {
  	case 3: h ^= data[2] << 16;
  	case 2: h ^= data[1] << 8;
  	case 1: h ^= data[0];
  			h *= m;
  	};
  
  	h ^= h >> 13;
  	h *= m;
  	h ^= h >> 15;
  
  	return h;
  }
  #else
  /*
  	Cross-platform version of Murmurhash3
  	http://code.google.com/p/smhasher/wiki/MurmurHash3
  	by Austin Appleby (aappleby@gmail.com)
  
  	This code is on the public domain.
  */
  uint32_t git__hash(const void *key, int len, uint32_t seed)
  {
  
  #define MURMUR_BLOCK() {\
  	k1 *= c1; \
  	k1 = git__rotl(k1,11);\
  	k1 *= c2;\
  	h1 ^= k1;\
  	h1 = h1*3 + 0x52dce729;\
  	c1 = c1*5 + 0x7b7d159c;\
  	c2 = c2*5 + 0x6bce6396;\
  }
  
  	const uint8_t *data = (const uint8_t*)key;
  	const int nblocks = len / 4;
  
  	const uint32_t *blocks = (const uint32_t *)(data + nblocks * 4);
  	const uint8_t *tail = (const uint8_t *)(data + nblocks * 4);
  
  	uint32_t h1 = 0x971e137b ^ seed;
  	uint32_t k1;
  
  	uint32_t c1 = 0x95543787;
  	uint32_t c2 = 0x2ad7eb25;
  
  	int i;
  
  	for (i = -nblocks; i; i++) {
  		k1 = blocks[i];
  		MURMUR_BLOCK();
  	}
  
  	k1 = 0;
  
  	switch(len & 3) {
  	case 3: k1 ^= tail[2] << 16;
  	case 2: k1 ^= tail[1] << 8;
  	case 1: k1 ^= tail[0];
  			MURMUR_BLOCK();
  	}
  
  	h1 ^= len;
  	h1 ^= h1 >> 16;
  	h1 *= 0x85ebca6b;
  	h1 ^= h1 >> 13;
  	h1 *= 0xc2b2ae35;
  	h1 ^= h1 >> 16;
  
  	return h1;
  }
  #endif
  
  /**
   * A modified `bsearch` from the BSD glibc.
   *
   * Copyright (c) 1990 Regents of the University of California.
   * All rights reserved.
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   * notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   * notice, this list of conditions and the following disclaimer in the
   * documentation and/or other materials provided with the distribution.
   * 3. [rescinded 22 July 1999]
   * 4. Neither the name of the University nor the names of its contributors
   * may be used to endorse or promote products derived from this software
   * without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   */
  int git__bsearch(
  	void **array,
  	size_t array_len,
  	const void *key,
  	int (*compare)(const void *, const void *),
  	size_t *position)
  {
  	size_t lim;
  	int cmp = -1;
  	void **part, **base = array;
  
  	for (lim = array_len; lim != 0; lim >>= 1) {
  		part = base + (lim >> 1);
  		cmp = (*compare)(key, *part);
  		if (cmp == 0) {
  			base = part;
  			break;
  		}
  		if (cmp > 0) { /* key > p; take right partition */
  			base = part + 1;
  			lim--;
  		} /* else take left partition */
  	}
  
  	if (position)
  		*position = (base - array);
  
  	return (cmp == 0) ? 0 : GIT_ENOTFOUND;
  }
  
  int git__bsearch_r(
  	void **array,
  	size_t array_len,
  	const void *key,
  	int (*compare_r)(const void *, const void *, void *),
  	void *payload,
  	size_t *position)
  {
  	size_t lim;
  	int cmp = -1;
  	void **part, **base = array;
  
  	for (lim = array_len; lim != 0; lim >>= 1) {
  		part = base + (lim >> 1);
  		cmp = (*compare_r)(key, *part, payload);
  		if (cmp == 0) {
  			base = part;
  			break;
  		}
  		if (cmp > 0) { /* key > p; take right partition */
  			base = part + 1;
  			lim--;
  		} /* else take left partition */
  	}
  
  	if (position)
  		*position = (base - array);
  
  	return (cmp == 0) ? 0 : GIT_ENOTFOUND;
  }
  
  /**
   * A strcmp wrapper
   *
   * We don't want direct pointers to the CRT on Windows, we may
   * get stdcall conflicts.
   */
  int git__strcmp_cb(const void *a, const void *b)
  {
  	const char *stra = (const char *)a;
  	const char *strb = (const char *)b;
  
  	return strcmp(stra, strb);
  }
  
  int git__parse_bool(int *out, const char *value)
  {
  	/* A missing value means true */
  	if (value == NULL ||
  		!strcasecmp(value, "true") ||
  		!strcasecmp(value, "yes") ||
  		!strcasecmp(value, "on")) {
  		*out = 1;
  		return 0;
  	}
  	if (!strcasecmp(value, "false") ||
  		!strcasecmp(value, "no") ||
  		!strcasecmp(value, "off") ||
  		value[0] == '\0') {
  		*out = 0;
  		return 0;
  	}
  
  	return -1;
  }
  
  size_t git__unescape(char *str)
  {
  	char *scan, *pos = str;
  
  	for (scan = str; *scan; pos++, scan++) {
  		if (*scan == '\\' && *(scan + 1) != '\0')
  			scan++; /* skip '\' but include next char */
  		if (pos != scan)
  			*pos = *scan;
  	}
  
  	if (pos != scan) {
  		*pos = '\0';
  	}
  
  	return (pos - str);
  }
  
  #if defined(GIT_WIN32) || defined(BSD)
  typedef struct {
  	git__sort_r_cmp cmp;
  	void *payload;
  } git__qsort_r_glue;
  
  static int GIT_STDLIB_CALL git__qsort_r_glue_cmp(
  	void *payload, const void *a, const void *b)
  {
  	git__qsort_r_glue *glue = payload;
  	return glue->cmp(a, b, glue->payload);
  }
  #endif
  
  void git__qsort_r(
  	void *els, size_t nel, size_t elsize, git__sort_r_cmp cmp, void *payload)
  {
  #if defined(__MINGW32__)
  	git__insertsort_r(els, nel, elsize, NULL, cmp, payload);
  #elif defined(GIT_WIN32)
  	git__qsort_r_glue glue = { cmp, payload };
  	qsort_s(els, nel, elsize, git__qsort_r_glue_cmp, &glue);
  #elif defined(BSD)
  	git__qsort_r_glue glue = { cmp, payload };
  	qsort_r(els, nel, elsize, &glue, git__qsort_r_glue_cmp);
  #else
  	qsort_r(els, nel, elsize, cmp, payload);
  #endif
  }
  
  void git__insertsort_r(
  	void *els, size_t nel, size_t elsize, void *swapel,
  	git__sort_r_cmp cmp, void *payload)
  {
  	uint8_t *base = els;
  	uint8_t *end = base + nel * elsize;
  	uint8_t *i, *j;
  	bool freeswap = !swapel;
  
  	if (freeswap)
  		swapel = git__malloc(elsize);
  
  	for (i = base + elsize; i < end; i += elsize)
  		for (j = i; j > base && cmp(j, j - elsize, payload) < 0; j -= elsize) {
  			memcpy(swapel, j, elsize);
  			memcpy(j, j - elsize, elsize);
  			memcpy(j - elsize, swapel, elsize);
  		}
  
  	if (freeswap)
  		git__free(swapel);
  }
  