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
|
/* quirc -- QR-code recognition library
* Copyright (C) 2010-2012 Daniel Beer <dlbeer@gmail.com>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <stdlib.h>
#include <string.h>
#include "quirc_internal.h"
const char *quirc_version(void)
{
return "1.0";
}
struct quirc *quirc_new(void)
{
struct quirc *q = malloc(sizeof(*q));
if (!q)
return NULL;
memset(q, 0, sizeof(*q));
return q;
}
void quirc_destroy(struct quirc *q)
{
free(q->image);
/* q->pixels may alias q->image when their type representation is of the
same size, so we need to be careful here to avoid a double free */
if (!QUIRC_PIXEL_ALIAS_IMAGE)
free(q->pixels);
free(q->flood_fill_vars);
free(q);
}
int quirc_resize(struct quirc *q, int w, int h)
{
uint8_t *image = NULL;
quirc_pixel_t *pixels = NULL;
size_t num_vars;
size_t vars_byte_size;
struct quirc_flood_fill_vars *vars = NULL;
/*
* XXX: w and h should be size_t (or at least unsigned) as negatives
* values would not make much sense. The downside is that it would break
* both the API and ABI. Thus, at the moment, let's just do a sanity
* check.
*/
if (w < 0 || h < 0)
goto fail;
/*
* alloc a new buffer for q->image. We avoid realloc(3) because we want
* on failure to be leave `q` in a consistant, unmodified state.
*/
image = calloc(w, h);
if (!image)
goto fail;
/* compute the "old" (i.e. currently allocated) and the "new"
(i.e. requested) image dimensions */
size_t olddim = q->w * q->h;
size_t newdim = w * h;
size_t min = (olddim < newdim ? olddim : newdim);
/*
* copy the data into the new buffer, avoiding (a) to read beyond the
* old buffer when the new size is greater and (b) to write beyond the
* new buffer when the new size is smaller, hence the min computation.
*/
(void)memcpy(image, q->image, min);
/* alloc a new buffer for q->pixels if needed */
if (!QUIRC_PIXEL_ALIAS_IMAGE) {
pixels = calloc(newdim, sizeof(quirc_pixel_t));
if (!pixels)
goto fail;
}
/*
* alloc the work area for the flood filling logic.
*
* the size was chosen with the following assumptions and observations:
*
* - rings are the regions which requires the biggest work area.
* - they consumes the most when they are rotated by about 45 degree.
* in that case, the necessary depth is about (2 * height_of_the_ring).
* - the maximum height of rings would be about 1/3 of the image height.
*/
if ((size_t)h * 2 / 2 != h) {
goto fail; /* size_t overflow */
}
num_vars = (size_t)h * 2 / 3;
if (num_vars == 0) {
num_vars = 1;
}
vars_byte_size = sizeof(*vars) * num_vars;
if (vars_byte_size / sizeof(*vars) != num_vars) {
goto fail; /* size_t overflow */
}
vars = malloc(vars_byte_size);
if (!vars)
goto fail;
/* alloc succeeded, update `q` with the new size and buffers */
q->w = w;
q->h = h;
free(q->image);
q->image = image;
if (!QUIRC_PIXEL_ALIAS_IMAGE) {
free(q->pixels);
q->pixels = pixels;
}
free(q->flood_fill_vars);
q->flood_fill_vars = vars;
q->num_flood_fill_vars = num_vars;
return 0;
/* NOTREACHED */
fail:
free(image);
free(pixels);
free(vars);
return -1;
}
int quirc_count(const struct quirc *q)
{
return q->num_grids;
}
static const char *const error_table[] = {
[QUIRC_SUCCESS] = "Success",
[QUIRC_ERROR_INVALID_GRID_SIZE] = "Invalid grid size",
[QUIRC_ERROR_INVALID_VERSION] = "Invalid version",
[QUIRC_ERROR_FORMAT_ECC] = "Format data ECC failure",
[QUIRC_ERROR_DATA_ECC] = "ECC failure",
[QUIRC_ERROR_UNKNOWN_DATA_TYPE] = "Unknown data type",
[QUIRC_ERROR_DATA_OVERFLOW] = "Data overflow",
[QUIRC_ERROR_DATA_UNDERFLOW] = "Data underflow"
};
const char *quirc_strerror(quirc_decode_error_t err)
{
if (err >= 0 && err < sizeof(error_table) / sizeof(error_table[0]))
return error_table[err];
return "Unknown error";
}
|
