fix a fence post error validating a combing mode number
[imager.git] / limits.c
CommitLineData
77157728
TC
1/*
2=head1 NAME
3
4limits.c - manages data/functions for limiting the sizes of images read from files.
5
6=head1 SYNOPSIS
7
8 // user code
9 if (!i_set_image_file_limits(max_width, max_height, max_bytes)) {
10 // error
11 }
12 i_get_image_file_limits(&max_width, &max_height, &max_bytes);
13
14 // file reader implementations
15 if (!i_int_check_image_file_limits(width, height, channels, sizeof(i_sample_t))) {
16 // error handling
17 }
18
19=head1 DESCRIPTION
20
21Manage limits for image files read by Imager.
22
23Setting a value of zero means that limit will be ignored.
12db268a
TC
24
25=over
26
27=cut
77157728
TC
28 */
29
d896d49c 30#define IMAGER_NO_CONTEXT
92bda632 31#include "imageri.h"
77157728 32
87deb14c 33/*
abffffed
TC
34=item im_set_image_file_limits(ctx, width, height, bytes)
35X<im_set_image_file_limits API>X<i_set_image_file_limits API>
87deb14c 36=category Files
abffffed 37=synopsis im_set_image_file_limits(aIMCTX, 500, 500, 1000000);
87deb14c
TC
38=synopsis i_set_image_file_limits(500, 500, 1000000);
39
40Set limits on the sizes of images read by Imager.
41
42Setting a limit to 0 means that limit is ignored.
43
44Negative limits result in failure.
45
8d14daab
TC
46Parameters:
47
48=over
49
50=item *
51
52i_img_dim width, height - maximum width and height.
53
54=item *
55
85cae6e7
TC
56size_t bytes - maximum size in memory in bytes. A value of zero sets
57this limit to one gigabyte.
8d14daab
TC
58
59=back
60
87deb14c
TC
61Returns non-zero on success.
62
abffffed
TC
63Also callable as C<i_set_image_file_limits(width, height, bytes)>.
64
87deb14c
TC
65=cut
66*/
67
77157728 68int
d896d49c 69im_set_image_file_limits(pIMCTX, i_img_dim width, i_img_dim height, size_t bytes) {
77157728
TC
70 i_clear_error();
71
72 if (width < 0) {
73 i_push_error(0, "width must be non-negative");
74 return 0;
75 }
76 if (height < 0) {
77 i_push_error(0, "height must be non-negative");
78 return 0;
79 }
80 if (bytes < 0) {
81 i_push_error(0, "bytes must be non-negative");
82 return 0;
83 }
84
d896d49c
TC
85 aIMCTX->max_width = width;
86 aIMCTX->max_height = height;
87 aIMCTX->max_bytes = bytes ? bytes : DEF_BYTES_LIMIT;
77157728
TC
88
89 return 1;
90}
91
87deb14c 92/*
abffffed
TC
93=item im_get_image_file_limits(ctx, &width, &height, &bytes)
94X<im_get_image_file_limits API>X<i_get_image_file_limits>
87deb14c 95=category Files
abffffed 96=synopsis im_get_image_file_limits(aIMCTX, &width, &height, &bytes)
87deb14c
TC
97=synopsis i_get_image_file_limits(&width, &height, &bytes)
98
99Retrieves the file limits set by i_set_image_file_limits().
100
8d14daab
TC
101=over
102
103=item *
104
105i_img_dim *width, *height - the maximum width and height of the image.
106
107=item *
108
109size_t *bytes - size in memory of the image in bytes.
110
111=back
112
abffffed
TC
113Also callable as C<i_get_image_file_limits(&width, &height, &bytes)>.
114
87deb14c
TC
115=cut
116*/
117
77157728 118int
d896d49c
TC
119im_get_image_file_limits(pIMCTX, i_img_dim *width, i_img_dim *height, size_t *bytes) {
120 im_clear_error(aIMCTX);
77157728 121
d896d49c
TC
122 *width = aIMCTX->max_width;
123 *height = aIMCTX->max_height;
124 *bytes = aIMCTX->max_bytes;
77157728
TC
125
126 return 1;
127}
128
87deb14c 129/*
abffffed
TC
130=item im_int_check_image_file_limits(width, height, channels, sample_size)
131X<im_int_check_image_file_limits API>X<i_int_check_image_file_limits>
87deb14c 132=category Files
abffffed
TC
133=synopsis im_int_check_image_file_limits(aIMCTX, width, height, channels, sizeof(i_sample_t))
134=synopsis i_int_check_image_file_limits(width, height, channels, sizeof(i_sample_t))
87deb14c
TC
135
136Checks the size of a file in memory against the configured image file
137limits.
138
139This also range checks the values to those permitted by Imager and
140checks for overflows in calculating the size.
141
142Returns non-zero if the file is within limits.
143
144This function is intended to be called by image file read functions.
145
abffffed
TC
146Also callable as C<i_int_check_image_file_limits(width, height, channels, sizeof(i_sample_t)>.
147
87deb14c
TC
148=cut
149*/
150
77157728 151int
d896d49c 152im_int_check_image_file_limits(pIMCTX, i_img_dim width, i_img_dim height, int channels, size_t sample_size) {
8d14daab 153 size_t bytes;
d896d49c 154 im_clear_error(aIMCTX);
77157728
TC
155
156 if (width <= 0) {
d896d49c 157 im_push_errorf(aIMCTX, 0, "file size limit - image width of %" i_DF " is not positive",
8d14daab 158 i_DFc(width));
77157728
TC
159 return 0;
160 }
d896d49c
TC
161 if (aIMCTX->max_width && width > aIMCTX->max_width) {
162 im_push_errorf(aIMCTX, 0, "file size limit - image width of %" i_DF " exceeds limit of %" i_DF,
163 i_DFc(width), i_DFc(aIMCTX->max_width));
77157728
TC
164 return 0;
165 }
166
167 if (height <= 0) {
d896d49c 168 im_push_errorf(aIMCTX, 0, "file size limit - image height of %" i_DF " is not positive",
8d14daab 169 i_DFc(height));
77157728
TC
170 return 0;
171 }
172
d896d49c
TC
173 if (aIMCTX->max_height && height > aIMCTX->max_height) {
174 im_push_errorf(aIMCTX, 0, "file size limit - image height of %" i_DF
175 " exceeds limit of %" i_DF, i_DFc(height), i_DFc(aIMCTX->max_height));
77157728
TC
176 return 0;
177 }
178
179 if (channels < 1 || channels > MAXCHANNELS) {
d896d49c 180 im_push_errorf(aIMCTX, 0, "file size limit - channels %d out of range",
77157728
TC
181 channels);
182 return 0;
183 }
184
185 if (sample_size < 1 || sample_size > sizeof(long double)) {
d896d49c 186 im_push_errorf(aIMCTX, 0, "file size limit - sample_size %ld out of range",
8d14daab 187 (long)sample_size);
77157728
TC
188 return 0;
189 }
190
191 /* This overflow check is a bit more paranoid than usual.
192 We don't protect it under max_bytes since we always want to check
193 for overflow.
194 */
5caa40a6 195 bytes = width * height * channels * sample_size;
77157728
TC
196 if (bytes / width != height * channels * sample_size
197 || bytes / height != width * channels * sample_size) {
d896d49c 198 im_push_error(aIMCTX, 0, "file size limit - integer overflow calculating storage");
77157728
TC
199 return 0;
200 }
d896d49c
TC
201 if (aIMCTX->max_bytes) {
202 if (bytes > aIMCTX->max_bytes) {
203 im_push_errorf(aIMCTX, 0, "file size limit - storage size of %lu "
8d14daab 204 "exceeds limit of %lu", (unsigned long)bytes,
d896d49c 205 (unsigned long)aIMCTX->max_bytes);
77157728
TC
206 return 0;
207 }
208 }
209
210 return 1;
211}