src/util.h

   1 /*
   2  * Copyright (C) 2009-2012 the libgit2 contributors
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7 #ifndef INCLUDE_util_h__
   8 #define INCLUDE_util_h__
   9
  10 #define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
  11 #define bitsizeof(x) (CHAR_BIT * sizeof(x))
  12 #define MSB(x, bits) ((x) & (~0ULL << (bitsizeof(x) - (bits))))
  13 #ifndef min
  14 # define min(a,b) ((a) < (b) ? (a) : (b))
  15 #endif
  16
  17 /*
  18  * Custom memory allocation wrappers
  19  * that set error code and error message
  20  * on allocation failure
  21  */
  22 GIT_INLINE(void *) git__malloc(size_t len)
  23 {
  24         void *ptr = malloc(len);
  25         if (!ptr)
  26                 git__throw(GIT_ENOMEM, "Out of memory. Failed to allocate %d bytes.", (int)len);
  27         return ptr;
  28 }
  29
  30 GIT_INLINE(void *) git__calloc(size_t nelem, size_t elsize)
  31 {
  32         void *ptr = calloc(nelem, elsize);
  33         if (!ptr)
  34                 git__throw(GIT_ENOMEM, "Out of memory. Failed to allocate %d bytes.", (int)elsize);
  35         return ptr;
  36 }
  37
  38 GIT_INLINE(char *) git__strdup(const char *str)
  39 {
  40         char *ptr = strdup(str);
  41         if (!ptr)
  42                 git__throw(GIT_ENOMEM, "Out of memory. Failed to duplicate string");
  43         return ptr;
  44 }
  45
  46 GIT_INLINE(char *) git__strndup(const char *str, size_t n)
  47 {
  48         size_t length;
  49         char *ptr;
  50
  51         length = strlen(str);
  52         if (n < length)
  53                 length = n;
  54
  55         ptr = (char*)malloc(length + 1);
  56         if (!ptr) {
  57                 git__throw(GIT_ENOMEM, "Out of memory. Failed to duplicate string");
  58                 return NULL;
  59         }
  60
  61         memcpy(ptr, str, length);
  62         ptr[length] = '\0';
  63
  64         return ptr;
  65 }
  66
  67 GIT_INLINE(void *) git__realloc(void *ptr, size_t size)
  68 {
  69         void *new_ptr = realloc(ptr, size);
  70         if (!new_ptr)
  71                 git__throw(GIT_ENOMEM, "Out of memory. Failed to allocate %d bytes.", (int)size);
  72         return new_ptr;
  73 }
  74
  75 #define git__free(ptr) free(ptr)
  76
  77 extern int git__prefixcmp(const char *str, const char *prefix);
  78 extern int git__suffixcmp(const char *str, const char *suffix);
  79
  80 extern int git__strtol32(int32_t *n, const char *buff, const char **end_buf, int base);
  81 extern int git__strtol64(int64_t *n, const char *buff, const char **end_buf, int base);
  82
  83 extern void git__hexdump(const char *buffer, size_t n);
  84 extern uint32_t git__hash(const void *key, int len, uint32_t seed);
  85
  86 /** @return true if p fits into the range of a size_t */
  87 GIT_INLINE(int) git__is_sizet(git_off_t p)
  88 {
  89         size_t r = (size_t)p;
  90         return p == (git_off_t)r;
  91 }
  92
  93 /* 32-bit cross-platform rotl */
  94 #ifdef _MSC_VER /* use built-in method in MSVC */
  95 #       define git__rotl(v, s) (uint32_t)_rotl(v, s)
  96 #else /* use bitops in GCC; with o2 this gets optimized to a rotl instruction */
  97 #       define git__rotl(v, s) (uint32_t)(((uint32_t)(v) << (s)) | ((uint32_t)(v) >> (32 - (s))))
  98 #endif
  99
 100 extern char *git__strtok(char **end, const char *sep);
 101
 102 extern void git__strntolower(char *str, size_t len);
 103 extern void git__strtolower(char *str);
 104
 105 GIT_INLINE(const char *) git__next_line(const char *s)
 106 {
 107         while (*s && *s != '\n') s++;
 108         while (*s == '\n' || *s == '\r') s++;
 109         return s;
 110 }
 111
 112 extern int git__fnmatch(const char *pattern, const char *name, int flags);
 113
 114 extern void git__tsort(void **dst, size_t size, int (*cmp)(const void *, const void *));
 115
 116 extern int git__bsearch(
 117         void **array,
 118         size_t array_len,
 119         const void *key,
 120         int (*compare)(const void *, const void *),
 121         size_t *position);
 122
 123 extern int git__strcmp_cb(const void *a, const void *b);
 124
 125 typedef struct {
 126         short refcount;
 127         void *owner;
 128 } git_refcount;
 129
 130 typedef void (*git_refcount_freeptr)(void *r);
 131
 132 #define GIT_REFCOUNT_INC(r) { \
 133         ((git_refcount *)(r))->refcount++; \
 134 }
 135
 136 #define GIT_REFCOUNT_DEC(_r, do_free) { \
 137         git_refcount *r = (git_refcount *)(_r); \
 138         r->refcount--; \
 139         if (r->refcount <= 0 && r->owner == NULL) { do_free(_r); } \
 140 }
 141
 142 #define GIT_REFCOUNT_OWN(r, o) { \
 143         ((git_refcount *)(r))->owner = o; \
 144 }
 145
 146 #define GIT_REFCOUNT_OWNER(r) (((git_refcount *)(r))->owner)
 147
 148 static signed char from_hex[] = {
 149 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 00 */
 150 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 10 */
 151 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 20 */
 152  0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, /* 30 */
 153 -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 40 */
 154 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 50 */
 155 -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 60 */
 156 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 70 */
 157 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 80 */
 158 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* 90 */
 159 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* a0 */
 160 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* b0 */
 161 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* c0 */
 162 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* d0 */
 163 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* e0 */
 164 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* f0 */
 165 };
 166
 167 GIT_INLINE(int) git__fromhex(char h)
 168 {
 169         return from_hex[(unsigned char) h];
 170 }
 171
 172 #endif /* INCLUDE_util_h__ */