src/buffer.h

   1 #ifndef _BUFFER_H_
   2 #define _BUFFER_H_
   3 #include "first.h"
   4
   5 #include "settings.h"
   6
   7 #include <stdlib.h>
   8 #include <sys/types.h>
   9 #include <stdio.h>
  10 #include <time.h>
  11
  12 #if defined HAVE_STDINT_H
  13 # include <stdint.h>
  14 #elif defined HAVE_INTTYPES_H
  15 # include <inttypes.h>
  16 #endif
  17
  18 /* generic string + binary data container; contains a terminating 0 in both
  19  * cases
  20  *
  21  * used == 0 indicates a special "empty" state (unset config values); ptr
  22  * might be NULL too then. otherwise an empty string has used == 1 (and ptr[0]
  23  * == 0);
  24  *
  25  * copy/append functions will ensure used >= 1 (i.e. never leave it in the
  26  * special empty state); only buffer_copy_buffer will copy the special empty
  27  * state.
  28  */
  29 typedef struct {
  30         char *ptr;
  31
  32         /* "used" includes a terminating 0 */
  33         size_t used;
  34         /* size of allocated buffer at *ptr */
  35         size_t size;
  36 } buffer;
  37
  38 /* create new buffer; either empty or copy given data */
  39 buffer* buffer_init(void);
  40 buffer* buffer_init_buffer(const buffer *src); /* src can  be NULL */
  41 buffer* buffer_init_string(const char *str); /* str can  be NULL */
  42
  43 void buffer_free(buffer *b); /* b can be NULL */
  44 /* truncates to used == 0; frees large buffers, might keep smaller ones for reuse */
  45 void buffer_reset(buffer *b); /* b can be NULL */
  46
  47 /* reset b. if NULL != b && NULL != src, move src content to b. reset src. */
  48 void buffer_move(buffer *b, buffer *src);
  49
  50 /* make sure buffer is large enough to store a string of given size
  51  * and a terminating zero.
  52  * sets b to an empty string, and may drop old content.
  53  * @return b->ptr
  54  */
  55 char* buffer_string_prepare_copy(buffer *b, size_t size);
  56
  57 /* allocate buffer large enough to be able to append a string of given size
  58  * if b was empty (used == 0) it will contain an empty string (used == 1)
  59  * afterwards
  60  * "used" data is preserved; if not empty buffer must contain a
  61  * zero terminated string.
  62  */
  63 char* buffer_string_prepare_append(buffer *b, size_t size);
  64
  65 /* use after prepare_(copy,append) when you have written data to the buffer
  66  * to increase the buffer length by size. also sets the terminating zero.
  67  * requires enough space is present for the terminating zero (prepare with the
  68  * same size to be sure).
  69  */
  70 void buffer_commit(buffer *b, size_t size);
  71
  72 /* sets string length:
  73  * - always stores a terminating zero to terminate the "new" string
  74  * - does not modify the string data apart from terminating zero
  75  * - reallocates the buffer iff needed
  76  */
  77 void buffer_string_set_length(buffer *b, size_t len);
  78
  79 void buffer_copy_string(buffer *b, const char *s);
  80 void buffer_copy_string_len(buffer *b, const char *s, size_t s_len);
  81 void buffer_copy_buffer(buffer *b, const buffer *src);
  82 /* convert input to hex and store in buffer */
  83 void buffer_copy_string_hex(buffer *b, const char *in, size_t in_len);
  84
  85 void buffer_append_string(buffer *b, const char *s);
  86 void buffer_append_string_len(buffer *b, const char *s, size_t s_len);
  87 void buffer_append_string_buffer(buffer *b, const buffer *src);
  88
  89 void buffer_append_uint_hex(buffer *b, uintmax_t len);
  90 void buffer_append_int(buffer *b, intmax_t val);
  91 void buffer_copy_int(buffer *b, intmax_t val);
  92
  93 void buffer_append_strftime(buffer *b, const char *format, const struct tm *tm);
  94
  95 /* '-', log_10 (2^bits) = bits * log 2 / log 10 < bits * 0.31, terminating 0 */
  96 #define LI_ITOSTRING_LENGTH (2 + (8 * sizeof(intmax_t) * 31 + 99) / 100)
  97
  98 void li_itostrn(char *buf, size_t buf_len, intmax_t val);
  99 void li_itostr(char *buf, intmax_t val); /* buf must have at least LI_ITOSTRING_LENGTH bytes */
 100 void li_utostrn(char *buf, size_t buf_len, uintmax_t val);
 101 void li_utostr(char *buf, uintmax_t val); /* buf must have at least LI_ITOSTRING_LENGTH bytes */
 102
 103 /* buf must be (at least) 2*s_len + 1 big. uses lower-case hex letters. */
 104 void li_tohex(char *buf, const char *s, size_t s_len);
 105
 106 char * buffer_search_string_len(buffer *b, const char *needle, size_t len);
 107
 108 /* NULL buffer or empty buffer (used == 0);
 109  * unset "string" (buffer) config options are initialized to used == 0,
 110  * while setting an empty string leads to used == 1
 111  */
 112 int buffer_is_empty(const buffer *b);
 113 /* NULL buffer, empty buffer (used == 0) or empty string (used == 1) */
 114 int buffer_string_is_empty(const buffer *b);
 115
 116 int buffer_is_equal(const buffer *a, const buffer *b);
 117 int buffer_is_equal_right_len(const buffer *a, const buffer *b, size_t len);
 118 int buffer_is_equal_string(const buffer *a, const char *s, size_t b_len);
 119 int buffer_is_equal_caseless_string(const buffer *a, const char *s, size_t b_len);
 120 int buffer_caseless_compare(const char *a, size_t a_len, const char *b, size_t b_len);
 121
 122 typedef enum {
 123         ENCODING_REL_URI, /* for coding a rel-uri (/with space/and%percent) nicely as part of a href */
 124         ENCODING_REL_URI_PART, /* same as ENC_REL_URL plus coding / too as %2F */
 125         ENCODING_HTML,         /* & becomes &amp; and so on */
 126         ENCODING_MINIMAL_XML,  /* minimal encoding for xml */
 127         ENCODING_HEX,          /* encode string as hex */
 128         ENCODING_HTTP_HEADER   /* encode \n with \t\n */
 129 } buffer_encoding_t;
 130
 131 void buffer_append_string_encoded(buffer *b, const char *s, size_t s_len, buffer_encoding_t encoding);
 132
 133 /* escape non-printable characters; simple escapes for \t, \r, \n; fallback to \xCC */
 134 void buffer_append_string_c_escaped(buffer *b, const char *s, size_t s_len);
 135
 136 /* to upper case, replace non alpha-numerics with '_'; if is_http_header prefix with "HTTP_" unless s is "content-type" */
 137 void buffer_copy_string_encoded_cgi_varnames(buffer *b, const char *s, size_t s_len, int is_http_header);
 138
 139 void buffer_urldecode_path(buffer *url);
 140 void buffer_urldecode_query(buffer *url);
 141 void buffer_path_simplify(buffer *dest, buffer *src);
 142
 143 void buffer_to_lower(buffer *b);
 144 void buffer_to_upper(buffer *b);
 145
 146
 147 /** deprecated */
 148 char hex2int(unsigned char c);
 149 char int2hex(char i);
 150
 151 int light_isdigit(int c);
 152 int light_isxdigit(int c);
 153 int light_isalpha(int c);
 154 int light_isalnum(int c);
 155
 156 static inline size_t buffer_string_length(const buffer *b); /* buffer string length without terminating 0 */
 157 static inline size_t buffer_string_space(const buffer *b); /* maximum length of string that can be stored without reallocating */
 158 static inline void buffer_append_slash(buffer *b); /* append '/' no non-empty strings not ending in '/' */
 159
 160 #define BUFFER_APPEND_STRING_CONST(x, y) \
 161         buffer_append_string_len(x, y, sizeof(y) - 1)
 162
 163 #define BUFFER_COPY_STRING_CONST(x, y) \
 164         buffer_copy_string_len(x, y, sizeof(y) - 1)
 165
 166 #define CONST_STR_LEN(x) x, (x) ? sizeof(x) - 1 : 0
 167 #define CONST_BUF_LEN(x) ((x) ? (x)->ptr : NULL), buffer_string_length(x)
 168
 169
 170 void print_backtrace(FILE *file);
 171 void log_failed_assert(const char *filename, unsigned int line, const char *msg) LI_NORETURN;
 172 #define force_assert(x) do { if (!(x)) log_failed_assert(__FILE__, __LINE__, "assertion failed: " #x); } while(0)
 173 #define SEGFAULT() log_failed_assert(__FILE__, __LINE__, "aborted");
 174
 175 /* inline implementations */
 176
 177 static inline size_t buffer_string_length(const buffer *b) {
 178         return NULL != b && 0 != b->used ? b->used - 1 : 0;
 179 }
 180
 181 static inline size_t buffer_string_space(const buffer *b) {
 182         if (NULL == b || b->size == 0) return 0;
 183         if (0 == b->used) return b->size - 1;
 184         return b->size - b->used;
 185 }
 186
 187 static inline void buffer_append_slash(buffer *b) {
 188         size_t len = buffer_string_length(b);
 189         if (len > 0 && '/' != b->ptr[len-1]) BUFFER_APPEND_STRING_CONST(b, "/");
 190 }
 191
 192 #endif