src/basic/string-util.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 #include <alloca.h>
   5 #include <stdbool.h>
   6 #include <stddef.h>
   7 #include <string.h>
   8
   9 #include "alloc-util.h"
  10 #include "macro.h"
  11
  12 /* What is interpreted as whitespace? */
  13 #define WHITESPACE        " \t\n\r"
  14 #define NEWLINE           "\n\r"
  15 #define QUOTES            "\"\'"
  16 #define COMMENTS          "#;"
  17 #define GLOB_CHARS        "*?["
  18 #define DIGITS            "0123456789"
  19 #define LOWERCASE_LETTERS "abcdefghijklmnopqrstuvwxyz"
  20 #define UPPERCASE_LETTERS "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
  21 #define LETTERS           LOWERCASE_LETTERS UPPERCASE_LETTERS
  22 #define ALPHANUMERICAL    LETTERS DIGITS
  23 #define HEXDIGITS         DIGITS "abcdefABCDEF"
  24
  25 #define streq(a,b) (strcmp((a),(b)) == 0)
  26 #define strneq(a, b, n) (strncmp((a), (b), (n)) == 0)
  27 #define strcaseeq(a,b) (strcasecmp((a),(b)) == 0)
  28 #define strncaseeq(a, b, n) (strncasecmp((a), (b), (n)) == 0)
  29
  30 int strcmp_ptr(const char *a, const char *b) _pure_;
  31
  32 static inline bool streq_ptr(const char *a, const char *b) {
  33         return strcmp_ptr(a, b) == 0;
  34 }
  35
  36 static inline const char* strempty(const char *s) {
  37         return s ?: "";
  38 }
  39
  40 static inline const char* strnull(const char *s) {
  41         return s ?: "(null)";
  42 }
  43
  44 static inline const char *strna(const char *s) {
  45         return s ?: "n/a";
  46 }
  47
  48 static inline bool isempty(const char *p) {
  49         return !p || !p[0];
  50 }
  51
  52 static inline const char *empty_to_null(const char *p) {
  53         return isempty(p) ? NULL : p;
  54 }
  55
  56 static inline const char *empty_to_dash(const char *str) {
  57         return isempty(str) ? "-" : str;
  58 }
  59
  60 static inline bool empty_or_dash(const char *str) {
  61         return !str ||
  62                 str[0] == 0 ||
  63                 (str[0] == '-' && str[1] == 0);
  64 }
  65
  66 static inline const char *empty_or_dash_to_null(const char *p) {
  67         return empty_or_dash(p) ? NULL : p;
  68 }
  69
  70 static inline char *startswith(const char *s, const char *prefix) {
  71         size_t l;
  72
  73         l = strlen(prefix);
  74         if (strncmp(s, prefix, l) == 0)
  75                 return (char*) s + l;
  76
  77         return NULL;
  78 }
  79
  80 static inline char *startswith_no_case(const char *s, const char *prefix) {
  81         size_t l;
  82
  83         l = strlen(prefix);
  84         if (strncasecmp(s, prefix, l) == 0)
  85                 return (char*) s + l;
  86
  87         return NULL;
  88 }
  89
  90 char *endswith(const char *s, const char *postfix) _pure_;
  91 char *endswith_no_case(const char *s, const char *postfix) _pure_;
  92
  93 char *first_word(const char *s, const char *word) _pure_;
  94
  95 typedef enum SplitFlags {
  96         SPLIT_QUOTES                     = 0x01 << 0,
  97         SPLIT_RELAX                      = 0x01 << 1,
  98 } SplitFlags;
  99
 100 const char* split(const char **state, size_t *l, const char *separator, SplitFlags flags);
 101
 102 #define FOREACH_WORD(word, length, s, state)                            \
 103         _FOREACH_WORD(word, length, s, WHITESPACE, 0, state)
 104
 105 #define FOREACH_WORD_SEPARATOR(word, length, s, separator, state)       \
 106         _FOREACH_WORD(word, length, s, separator, 0, state)
 107
 108 #define _FOREACH_WORD(word, length, s, separator, flags, state)         \
 109         for ((state) = (s), (word) = split(&(state), &(length), (separator), (flags)); (word); (word) = split(&(state), &(length), (separator), (flags)))
 110
 111 char *strappend(const char *s, const char *suffix);
 112 char *strnappend(const char *s, const char *suffix, size_t length);
 113
 114 char *strjoin_real(const char *x, ...) _sentinel_;
 115 #define strjoin(a, ...) strjoin_real((a), __VA_ARGS__, NULL)
 116
 117 #define strjoina(a, ...)                                                \
 118         ({                                                              \
 119                 const char *_appendees_[] = { a, __VA_ARGS__ };         \
 120                 char *_d_, *_p_;                                        \
 121                 size_t _len_ = 0;                                          \
 122                 size_t _i_;                                           \
 123                 for (_i_ = 0; _i_ < ELEMENTSOF(_appendees_) && _appendees_[_i_]; _i_++) \
 124                         _len_ += strlen(_appendees_[_i_]);              \
 125                 _p_ = _d_ = newa(char, _len_ + 1);                      \
 126                 for (_i_ = 0; _i_ < ELEMENTSOF(_appendees_) && _appendees_[_i_]; _i_++) \
 127                         _p_ = stpcpy(_p_, _appendees_[_i_]);            \
 128                 *_p_ = 0;                                               \
 129                 _d_;                                                    \
 130         })
 131
 132 char *strstrip(char *s);
 133 char *delete_chars(char *s, const char *bad);
 134 char *delete_trailing_chars(char *s, const char *bad);
 135 char *truncate_nl(char *s);
 136
 137 static inline char *skip_leading_chars(const char *s, const char *bad) {
 138
 139         if (!s)
 140                 return NULL;
 141
 142         if (!bad)
 143                 bad = WHITESPACE;
 144
 145         return (char*) s + strspn(s, bad);
 146 }
 147
 148 char ascii_tolower(char x);
 149 char *ascii_strlower(char *s);
 150 char *ascii_strlower_n(char *s, size_t n);
 151
 152 char ascii_toupper(char x);
 153 char *ascii_strupper(char *s);
 154
 155 int ascii_strcasecmp_n(const char *a, const char *b, size_t n);
 156 int ascii_strcasecmp_nn(const char *a, size_t n, const char *b, size_t m);
 157
 158 bool chars_intersect(const char *a, const char *b) _pure_;
 159
 160 static inline bool _pure_ in_charset(const char *s, const char* charset) {
 161         assert(s);
 162         assert(charset);
 163         return s[strspn(s, charset)] == '\0';
 164 }
 165
 166 bool string_has_cc(const char *p, const char *ok) _pure_;
 167
 168 char *ellipsize_mem(const char *s, size_t old_length_bytes, size_t new_length_columns, unsigned percent);
 169 static inline char *ellipsize(const char *s, size_t length, unsigned percent) {
 170         return ellipsize_mem(s, strlen(s), length, percent);
 171 }
 172
 173 char *cellescape(char *buf, size_t len, const char *s);
 174
 175 /* This limit is arbitrary, enough to give some idea what the string contains */
 176 #define CELLESCAPE_DEFAULT_LENGTH 64
 177
 178 char* strshorten(char *s, size_t l);
 179
 180 char *strreplace(const char *text, const char *old_string, const char *new_string);
 181
 182 char *strip_tab_ansi(char **ibuf, size_t *_isz, size_t highlight[2]);
 183
 184 char *strextend_with_separator(char **x, const char *separator, ...) _sentinel_;
 185
 186 #define strextend(x, ...) strextend_with_separator(x, NULL, __VA_ARGS__)
 187
 188 char *strrep(const char *s, unsigned n);
 189
 190 int split_pair(const char *s, const char *sep, char **l, char **r);
 191
 192 int free_and_strdup(char **p, const char *s);
 193 static inline int free_and_strdup_warn(char **p, const char *s) {
 194         if (free_and_strdup(p, s) < 0)
 195                 return log_oom();
 196         return 0;
 197 }
 198 int free_and_strndup(char **p, const char *s, size_t l);
 199
 200 char *string_erase(char *x);
 201
 202 char *string_free_erase(char *s);
 203 DEFINE_TRIVIAL_CLEANUP_FUNC(char *, string_free_erase);
 204 #define _cleanup_string_free_erase_ _cleanup_(string_free_erasep)
 205
 206 bool string_is_safe(const char *p) _pure_;
 207
 208 static inline size_t strlen_ptr(const char *s) {
 209         if (!s)
 210                 return 0;
 211
 212         return strlen(s);
 213 }
 214
 215 DISABLE_WARNING_STRINGOP_TRUNCATION;
 216 static inline void strncpy_exact(char *buf, const char *src, size_t buf_len) {
 217         strncpy(buf, src, buf_len);
 218 }
 219 REENABLE_WARNING;
 220
 221 /* Like startswith(), but operates on arbitrary memory blocks */
 222 static inline void *memory_startswith(const void *p, size_t sz, const char *token) {
 223         size_t n;
 224
 225         assert(token);
 226
 227         n = strlen(token);
 228         if (sz < n)
 229                 return NULL;
 230
 231         assert(p);
 232
 233         if (memcmp(p, token, n) != 0)
 234                 return NULL;
 235
 236         return (uint8_t*) p + n;
 237 }
 238
 239 /* Like startswith_no_case(), but operates on arbitrary memory blocks.
 240  * It works only for ASCII strings.
 241  */
 242 static inline void *memory_startswith_no_case(const void *p, size_t sz, const char *token) {
 243         size_t n, i;
 244
 245         assert(token);
 246
 247         n = strlen(token);
 248         if (sz < n)
 249                 return NULL;
 250
 251         assert(p);
 252
 253         for (i = 0; i < n; i++) {
 254                 if (ascii_tolower(((char *)p)[i]) != ascii_tolower(token[i]))
 255                         return NULL;
 256         }
 257
 258         return (uint8_t*) p + n;
 259 }