src/str.h

   1 /* dynamic string handling */
   2 /* Copyright (c) Olly Betts 1999, 2001, 2012, 2014, 2024
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18
  19 #ifndef SURVEX_INCLUDED_STR_H
  20 #define SURVEX_INCLUDED_STR_H
  21
  22 #include "osalloc.h"
  23 #include <string.h>
  24
  25 typedef struct {
  26     char *s;
  27     int len;
  28     int capacity; /* One less than the allocated size! */
  29 } string;
  30
  31 // string foo = S_INIT;
  32 #define S_INIT { NULL, 0, 0 }
  33
  34 void s_expand_(string *pstr, int addition);
  35
  36 /* Append a block of text with given length. */
  37 void s_catlen(string *pstr, const char *s, int s_len);
  38
  39 void s_catn(string *pstr, int n, char c);
  40
  41 /* Append another string. */
  42 inline void s_cats(string *pstr, const string *s) {
  43     s_catlen(pstr, s->s, s->len);
  44 }
  45
  46 /* Append a C string. */
  47 inline void s_cat(string *pstr, const char *s) {
  48     s_catlen(pstr, s, strlen(s));
  49 }
  50
  51 /* Append a character */
  52 inline void s_catchar(string *pstr, char c) {
  53     if (pstr->capacity == pstr->len) s_expand_(pstr, 1);
  54     pstr->s[pstr->len++] = c;
  55     pstr->s[pstr->len] = '\0';
  56 }
  57
  58 /* Truncate string to zero length (and ensure it isn't NULL). */
  59 inline void s_clear(string *pstr) {
  60     if (pstr->s == NULL) s_expand_(pstr, 0);
  61     pstr->len = 0;
  62     pstr->s[0] = '\0';
  63 }
  64
  65 /* Truncate string */
  66 inline void s_truncate(string *pstr, int new_len) {
  67     if (new_len < pstr->len) {
  68         pstr->len = new_len;
  69         pstr->s[new_len] = '\0';
  70     }
  71 }
  72
  73 /* Release allocated memory. */
  74 inline void s_free(string *pstr) {
  75     osfree(pstr->s);
  76     pstr->s = NULL;
  77     pstr->len = 0;
  78     pstr->capacity = 0;
  79 }
  80
  81 /* Steal the C string. */
  82 inline char *s_steal(string *pstr) {
  83     char *s = pstr->s;
  84     pstr->s = NULL;
  85     pstr->len = 0;
  86     pstr->capacity = 0;
  87     return s;
  88 }
  89
  90 /* Donate a malloc-ed C string. */
  91 inline void s_donate(string *pstr, char *s) {
  92     osfree(pstr->s);
  93     pstr->s = s;
  94     pstr->capacity = pstr->len = strlen(s);
  95 }
  96
  97 inline int s_len(const string *pstr) { return pstr->len; }
  98
  99 inline bool s_empty(const string *pstr) { return pstr->len == 0; }
 100
 101 inline const char *s_str(string *pstr) { return pstr->s; }
 102
 103 inline bool s_eqlen(const string *pstr, const char *s, int s_len) {
 104     return pstr->len == s_len && memcmp(pstr->s, s, s_len) == 0;
 105 }
 106
 107 inline bool s_eq(const string *pstr, const char *s) {
 108     return strcmp(pstr->s, s) == 0;
 109 }
 110
 111 #define S_EQ(PSTR, LITERAL) s_eqlen((PSTR), LITERAL, sizeof(LITERAL "") - 1)
 112
 113 #endif // SURVEX_INCLUDED_STR_H