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
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
/**
* scrotty — Screenshot program for Linux's TTY
*
* Copyright © 2014, 2015 Mattias Andrée (maandree@member.fsf.org)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "common.h"
#include "pattern.h"
/**
* Duplicate all '%':s in a buffer until the first occurrence of a zero byte.
*
* @param buf The buffer.
* @param n The size of the buffer.
* @return -1 if the buffer is too small, otherwise.
* the new position of the first zero byte.
*/
static ssize_t
duplicate_percents (char *restrict buf, size_t n)
{
size_t p = 0, pi, pc = 0, i;
/* Count number of '%':s. */
for (i = 0; buf[i]; i++)
if (buf[i] == '%')
pc++;
/* Check whether the string will overflow. */
if (i + pc > n)
return -1;
/* Duplicate all '%':s. */
for (pi = 0; pi < pc; pi++)
{
p = (size_t)(strchr (buf + p, '%') - buf);
memmove (buf + p + 1, buf + p, (i - (p - pi)) * sizeof (char));
p += 2;
}
return (ssize_t)(i + pi);
}
/**
* Parse and evaluate a --exec argument or filename pattern.
*
* If `path != NULL` than all non-escaped spaces in
* `pattern` will be stored as 255-bytes in `buf`.
*
* @param buf The output buffer.
* @param n The size of `buf`.
* @param pattern The pattern to evaluate.
* @param fbno The index of the framebuffer.
* @param width The width of the image/framebuffer.
* @param height The height of the image/framebuffer.
* @param path The filename of the saved image, `NULL`
* during the evaluation of the filename pattern.
* @return Zero on success, -1 on error.
*/
static int
try_evaluate (char *restrict buf, size_t n, const char *restrict pattern,
int fbno, long width, long height, const char *restrict path)
{
#define P(format, value) r = snprintf (buf + i, n - i, format "%zn", value, &j)
size_t i = 0;
ssize_t j = 0;
int percent = 0, backslash = 0, dollar = 0, r = 0;
char c;
char *fmt = NULL;
time_t t;
struct tm *tm;
int saved_errno;
/* Expand '$' and '\'. */
while ((i < n) && ((c = *pattern++)))
if (dollar)
{
dollar = 0;
if (path == NULL)
if ((c == 'f') || (c == 'n'))
continue;
if (c == 'i') P ("%i", fbno);
else if (c == 'f') P ("%s", path);
else if (c == 'n') P ("%s", strrchr (path, '/') ? (strrchr (path, '/') + 1) : path);
else if (c == 'p') P ("%ju", (uintmax_t)width * (uintmax_t)height);
else if (c == 'w') P ("%li", width);
else if (c == 'h') P ("%li", height);
else if (c == '$') r = 0, j = 1, buf[i] = '$';
else if ((r < 0) || (j <= 0))
return -1;
else if ((c == 'f') || (c == 'n'))
if (j = duplicate_percents (buf + i, n - i), j < 0)
goto enametoolong;
i += (size_t)j;
}
else if (backslash) buf[i++] = (c == 'n' ? '\n' : c), backslash = 0;
else if (percent) buf[i++] = c, percent = 0;
else if (c == '%') buf[i++] = c, percent = 1;
else if (c == '\\') backslash = 1;
else if (c == '$') dollar = 1;
else if (c == ' ') buf[i++] = path == NULL ? ' ' : (char)255; /* 255 is not valid in UTF-8. */
else buf[i++] = c;
if (i >= n)
goto enametoolong;
buf[i] = '\0';
/* Check whether there are any '%' to expand. */
if (strchr (buf, '%') == NULL)
return 0;
/* Copy the buffer so we can reuse the buffer and use its old content for the format. */
fmt = strdup (buf);
if (fmt == NULL)
goto fail;
/* Expand '%'. */
t = time (NULL);
tm = localtime (&t);
if (tm == NULL)
goto fail;
#ifdef __GNUC__
# pragma GCC diagnostic ignored "-Wformat-nonliteral"
#endif
if (strftime (buf, n, fmt, tm) == 0)
goto enametoolong; /* No errors are defined for `strftime`. What else can we do? */
free (fmt);
return 0;
enametoolong:
errno = ENAMETOOLONG;
fail:
saved_errno = errno;
free (fmt);
errno = saved_errno;
return -1;
}
/**
* Parse and evaluate a --exec argument or filename pattern.
*
* If `path != NULL` than all non-escaped spaces in
* `pattern` will be stored as 255-bytes in `buf`.
*
* @param pattern The pattern to evaluate.
* @param fbno The index of the framebuffer.
* @param width The width of the image/framebuffer.
* @param height The height of the image/framebuffer.
* @param path The filename of the saved image, `NULL`
* during the evaluation of the filename pattern.
* @return The constructed string, `NULL` on error.
*/
char*
evaluate (const char *restrict pattern, int fbno, long width,
long height, const char *restrict path)
{
char *buffer = NULL;
size_t size = 32;
void *new;
int saved_errno;
retry:
new = realloc (buffer, size * sizeof(char));
if (new == NULL)
goto fail;
buffer = new;
if (try_evaluate (buffer, size, pattern, fbno, width, height, path) < 0)
{
if (errno == ENAMETOOLONG)
goto retry;
size <<= 1;
goto fail;
}
return buffer;
fail:
saved_errno = errno;
free(buffer);
errno = saved_errno;
return NULL;
}
|
