cstring/include/cstring.h


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180

/// Fixed-size strings with value semantics.
#pragma once

#include <cassert.h>

#ifdef __linux__
#include <bsd/string.h>
#else
#include <string.h>
#endif
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>

// -----------------------------------------------------------------------------
// Fix-sized strings.

/// A fixed-size string.
/// The string is null-terminated so that it can be used with the usual C APIs.
#define DEF_STRING(STRING, SIZE)                                              \
  typedef struct STRING {                                                     \
    size_t length;                                                            \
    char   str[SIZE];                                                         \
  } STRING;                                                                   \
                                                                              \
  static const size_t STRING##_size = SIZE;                                   \
                                                                              \
  static inline const char* STRING##_cstr(const STRING* str) {                \
    return str->str;                                                          \
  }                                                                           \
                                                                              \
  static inline size_t STRING##_length(const STRING* str) {                   \
    return str->length;                                                       \
  }                                                                           \
                                                                              \
  static inline STRING STRING##_make(const char* cstr) {                      \
    if (!cstr) {                                                              \
      return (STRING){0};                                                     \
    } else {                                                                  \
      STRING str = (STRING){0};                                               \
      str.length = strlcpy(str.str, cstr, SIZE);                              \
      return str;                                                             \
    }                                                                         \
  }                                                                           \
                                                                              \
  static inline STRING STRING##_make_empty() { return (STRING){0}; }          \
                                                                              \
  static inline STRING STRING##_dirname(const STRING path) {                  \
    STRING str = path;                                                        \
    for (int i = str.length - 1; i >= 0; --i) {                               \
      if (str.str[i] == '/' || str.str[i] == '\\') {                          \
        str.str[i] = 0;                                                       \
        str.length = i;                                                       \
        return str;                                                           \
      } else {                                                                \
        str.str[i] = 0;                                                       \
      }                                                                       \
    }                                                                         \
    str        = (STRING){0};                                                 \
    str.str[0] = '.';                                                         \
    str.length = 1;                                                           \
    return str;                                                               \
  }                                                                           \
                                                                              \
  static inline void STRING##_append_cstr_len(                                \
      STRING* a, const char* b, const size_t b_length) {                      \
    ASSERT(a->length + b_length + 1 <= SIZE);                                 \
    strlcpy(a->str + a->length, b, SIZE - a->length);                         \
    a->length += b_length;                                                    \
  }                                                                           \
                                                                              \
  static inline void STRING##_append_cstr(STRING* a, const char* b) {         \
    STRING##_append_cstr_len(a, b, strlen(b));                                \
  }                                                                           \
                                                                              \
  static inline void STRING##_append(STRING* a, const STRING b) {             \
    STRING##_append_cstr_len(a, b.str, b.length);                             \
  }                                                                           \
                                                                              \
  static inline STRING STRING##_concat_cstr_len(                              \
      const STRING a, const char* b, const size_t b_length) {                 \
    ASSERT(a.length + b_length + 1 <= SIZE);                                  \
    STRING str = {0};                                                         \
    STRING##_append_cstr_len(&str, a.str, a.length);                          \
    STRING##_append_cstr_len(&str, b, b_length);                              \
    return str;                                                               \
  }                                                                           \
                                                                              \
  static inline STRING STRING##_concat_cstr(const STRING a, const char* b) {  \
    return STRING##_concat_cstr_len(a, b, strlen(b));                         \
  }                                                                           \
                                                                              \
  static inline STRING STRING##_concat(const STRING a, const STRING b) {      \
    return STRING##_concat_cstr_len(a, b.str, b.length);                      \
  }                                                                           \
                                                                              \
  static inline STRING STRING##_concat_path(const STRING a, const STRING b) { \
    return STRING##_concat(STRING##_concat_cstr(a, "/"), b);                  \
  }                                                                           \
                                                                              \
  static inline STRING STRING##_slice(                                        \
      const STRING a, const size_t start, const size_t end) {                 \
    ASSERT(start < a.length);                                                 \
    ASSERT(end <= a.length);                                                  \
    STRING str = {0};                                                         \
    strlcpy(str.str, &a.str[start], end - start);                             \
    return str;                                                               \
  }                                                                           \
                                                                              \
  static inline bool STRING##_eq_cstr_len(                                    \
      const STRING a, const char* b, size_t b_length) {                       \
    return (a.length == b_length) && strncmp(a.str, b, a.length) == 0;        \
  }                                                                           \
                                                                              \
  static inline bool STRING##_eq_cstr(const STRING a, const char* b) {        \
    return STRING##_eq_cstr_len(a, b, strlen(b));                             \
  }                                                                           \
                                                                              \
  static inline bool STRING##_eq(const STRING a, const STRING b) {            \
    return STRING##_eq_cstr_len(a, b.str, b.length);                          \
  }                                                                           \
                                                                              \
  static inline bool STRING##_empty(const STRING a) { return a.length == 0; } \
                                                                              \
  static inline STRING STRING##_itoa(int n) {                                 \
    STRING    str     = (STRING){0};                                          \
    const int written = snprintf(str.str, SIZE, "%d", n);                     \
    ASSERT(written >= 0);                                                     \
    str.length = (size_t)written;                                             \
    return str;                                                               \
  }                                                                           \
                                                                              \
  static inline uint64_t STRING##_hash(const STRING str) {                    \
    return cstring_hash(str.str);                                             \
  }

/// Return a hash of the given string.
static inline uint64_t cstring_hash(const char* str) {
  uint64_t hash = 0;
  for (size_t i = 0; i < strlen(str); ++i) {
    hash = (uint64_t)str[i] + (hash << 6) + (hash << 16) - hash;
  }
  return hash;
}

DEF_STRING(sstring, 32)    // Small.
DEF_STRING(mstring, 256)   // Medium.
DEF_STRING(lstring, 1024)  // Large.
DEF_STRING(xlstring, 4096) // Extra large.

// -----------------------------------------------------------------------------
// Dynamically-sized strings.

typedef struct string {
  const char* data;
  size_t      length;
} string;

/// Create a new string.
string string_new(const char*);

/// Delete the string.
void string_del(string*);

/// Get the string's length.
static inline size_t string_length(const string str) { return str.length; }

/// Get the string's data.
static inline const char* string_data(const string str) { return str.data; }

/// Concatenate two strings.
string string_concat(string left, string right);

/// Convert a size to string.
string string_from_size(size_t);

/// Convert and format a size to string.
/// The result uses B for bytes, K for kilobytes (1024), M for megabytes
/// (2**20), and G for gigabytes (2**30), with two decimal digits.
string string_format_size(size_t);