summaryrefslogtreecommitdiff
path: root/ext/json/fbuffer/fbuffer.h
blob: b5e47eec427538cb771d3a795669f8ab72e1fee3 (plain)
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
181
182
183
184
185

#ifndef _FBUFFER_H_
#define _FBUFFER_H_

#include "ruby.h"
#include <assert.h>

#ifndef RHASH_SIZE
#define RHASH_SIZE(hsh) (RHASH(hsh)->tbl->num_entries)
#endif

#ifndef RFLOAT_VALUE
#define RFLOAT_VALUE(val) (RFLOAT(val)->value)
#endif

#ifndef RARRAY_PTR
#define RARRAY_PTR(ARRAY) RARRAY(ARRAY)->ptr
#endif
#ifndef RARRAY_LEN
#define RARRAY_LEN(ARRAY) RARRAY(ARRAY)->len
#endif
#ifndef RSTRING_PTR
#define RSTRING_PTR(string) RSTRING(string)->ptr
#endif
#ifndef RSTRING_LEN
#define RSTRING_LEN(string) RSTRING(string)->len
#endif

#ifdef HAVE_RUBY_ENCODING_H
#include "ruby/encoding.h"
#define FORCE_UTF8(obj) rb_enc_associate((obj), rb_utf8_encoding())
#else
#define FORCE_UTF8(obj)
#endif

/* We don't need to guard objects for rbx, so let's do nothing at all. */
#ifndef RB_GC_GUARD
#define RB_GC_GUARD(object)
#endif

typedef struct FBufferStruct {
    unsigned long initial_length;
    char *ptr;
    unsigned long len;
    unsigned long capa;
} FBuffer;

#define FBUFFER_INITIAL_LENGTH_DEFAULT 1024

#define FBUFFER_PTR(fb) (fb->ptr)
#define FBUFFER_LEN(fb) (fb->len)
#define FBUFFER_CAPA(fb) (fb->capa)
#define FBUFFER_PAIR(fb) FBUFFER_PTR(fb), FBUFFER_LEN(fb)

static FBuffer *fbuffer_alloc(unsigned long initial_length);
static void fbuffer_free(FBuffer *fb);
static void fbuffer_clear(FBuffer *fb);
static void fbuffer_append(FBuffer *fb, const char *newstr, unsigned long len);
#ifdef JSON_GENERATOR
static void fbuffer_append_long(FBuffer *fb, long number);
#endif
static void fbuffer_append_char(FBuffer *fb, char newchr);
#ifdef JSON_GENERATOR
static FBuffer *fbuffer_dup(FBuffer *fb);
static VALUE fbuffer_to_s(FBuffer *fb);
#endif

static FBuffer *fbuffer_alloc(unsigned long initial_length)
{
    FBuffer *fb;
    if (initial_length <= 0) initial_length = FBUFFER_INITIAL_LENGTH_DEFAULT;
    fb = ALLOC(FBuffer);
    memset((void *) fb, 0, sizeof(FBuffer));
    fb->initial_length = initial_length;
    return fb;
}

static void fbuffer_free(FBuffer *fb)
{
    if (fb->ptr) ruby_xfree(fb->ptr);
    ruby_xfree(fb);
}

static void fbuffer_clear(FBuffer *fb)
{
    fb->len = 0;
}

static void fbuffer_inc_capa(FBuffer *fb, unsigned long requested)
{
    unsigned long required;

    if (!fb->ptr) {
        fb->ptr = ALLOC_N(char, fb->initial_length);
        fb->capa = fb->initial_length;
    }

    for (required = fb->capa; requested > required - fb->len; required <<= 1);

    if (required > fb->capa) {
        REALLOC_N(fb->ptr, char, required);
        fb->capa = required;
    }
}

static void fbuffer_append(FBuffer *fb, const char *newstr, unsigned long len)
{
    if (len > 0) {
        fbuffer_inc_capa(fb, len);
        MEMCPY(fb->ptr + fb->len, newstr, char, len);
        fb->len += len;
    }
}

#ifdef JSON_GENERATOR
static void fbuffer_append_str(FBuffer *fb, VALUE str)
{
    const char *newstr = StringValuePtr(str);
    unsigned long len = RSTRING_LEN(str);

    RB_GC_GUARD(str);

    fbuffer_append(fb, newstr, len);
}
#endif

static void fbuffer_append_char(FBuffer *fb, char newchr)
{
    fbuffer_inc_capa(fb, 1);
    *(fb->ptr + fb->len) = newchr;
    fb->len++;
}

#ifdef JSON_GENERATOR
static void freverse(char *start, char *end)
{
    char c;

    while (end > start) {
        c = *end, *end-- = *start, *start++ = c;
    }
}

static long fltoa(long number, char *buf)
{
    static char digits[] = "0123456789";
    long sign = number;
    char* tmp = buf;

    if (sign < 0) number = -number;
    do *tmp++ = digits[number % 10]; while (number /= 10);
    if (sign < 0) *tmp++ = '-';
    freverse(buf, tmp - 1);
    return tmp - buf;
}

static void fbuffer_append_long(FBuffer *fb, long number)
{
    char buf[20];
    unsigned long len = fltoa(number, buf);
    fbuffer_append(fb, buf, len);
}

static FBuffer *fbuffer_dup(FBuffer *fb)
{
    unsigned long len = fb->len;
    FBuffer *result;

    assert(len > 0);
    if (len > 0) {
        result = fbuffer_alloc(len);
        fbuffer_append(result, FBUFFER_PAIR(fb));
    }
    return result;
}

static VALUE fbuffer_to_s(FBuffer *fb)
{
    VALUE result = rb_str_new(FBUFFER_PAIR(fb));
    fbuffer_free(fb);
    FORCE_UTF8(result);
    return result;
}
#endif
#endif