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
|
/*
* add black as color #0 to a pcx file
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <ctype.h>
typedef struct {
unsigned size;
unsigned char *data;
unsigned real_size;
} file_data_t;
void help(void);
file_data_t read_file(char *name);
int is_pcx(file_data_t *fd);
int is_black(file_data_t *fd);
void write_data(file_data_t *fd, char *name);
void add_data(file_data_t *d, void *buffer, unsigned size);
void add_black(file_data_t *new, file_data_t *old);
file_data_t pcx_old = {};
file_data_t pcx_new = {};
int main(int argc, char **argv)
{
if(argc != 3) return 1;
pcx_old = read_file(argv[1]);
if(!is_pcx(&pcx_old)) return 2;
if(is_black(&pcx_old)) {
fprintf(stderr, "color 0 is black\n");
return 0;
}
add_black(&pcx_new, &pcx_old);
write_data(&pcx_new, argv[2]);
return 0;
}
file_data_t read_file(char *name)
{
file_data_t fd = { };
FILE *f;
if(!name) return fd;
f = fopen(name, "r");
if(!f) { perror(name); return fd; }
if(fseek(f, 0, SEEK_END)) {
perror(name);
exit(30);
}
fd.size = fd.real_size = ftell(f);
if(fseek(f, 0, SEEK_SET)) {
perror(name);
exit(30);
}
if(fd.size) {
fd.data = malloc(fd.size);
if(!fd.data) {
fprintf(stderr, "malloc failed\n");
exit(30);
}
}
if(fread(fd.data, 1, fd.size, f) != fd.size) {
perror(name);
exit(30);
}
fclose(f);
return fd;
}
int is_pcx(file_data_t *fd)
{
if(!fd->data || fd->size < 0x381) return 0;
if(
fd->data[0] != 10 ||
fd->data[1] != 5 ||
fd->data[2] != 1 ||
fd->data[3] != 8 ||
fd->data[fd->size - 0x301] != 12
) return 0;
return 1;
}
int is_black(file_data_t *fd)
{
return !(fd->data[fd->size - 0x300] || fd->data[fd->size - 0x300 + 1] || fd->data[fd->size - 0x300 + 2]);
}
void write_data(file_data_t *fd, char *name)
{
FILE *f;
if(!fd->size) return;
f = strcmp(name, "-") ? fopen(name, "w") : stdout;
if(!f) {
perror(name);
return;
}
if(fwrite(fd->data, fd->size, 1, f) != 1) {
perror(name); exit(3);
}
fclose(f);
}
void add_data(file_data_t *d, void *buffer, unsigned size)
{
if(!size || !d || !buffer) return;
if(d->size + size > d->real_size) {
d->real_size = d->size + size + 0x1000;
d->data = realloc(d->data, d->real_size);
if(!d->data) d->real_size = 0;
}
if(d->size + size <= d->real_size) {
memcpy(d->data + d->size, buffer, size);
d->size += size;
}
else {
fprintf(stderr, "Oops, out of memory? Aborted.\n");
exit(10);
}
}
void add_black(file_data_t *new, file_data_t *old)
{
int i, size;
unsigned char black[4] = { 12, 0, 0, 0 };
unsigned char *src = old->data + 0x80;
unsigned char c[1];
add_data(new, old->data, 0x80);
size = old->size - 0x381;
for(i = 0; i < size; i++) {
if(src[i] < 0xbf) {
*c = src[i] + 1;
add_data(new, c, 1);
}
else if(src[i] == 0xbf) {
*c = 0xc1;
add_data(new, c, 1);
*c = 0xc0;
add_data(new, c, 1);
}
else {
add_data(new, src + i, 1);
i++;
*c = src[i] + 1;
add_data(new, c, 1);
}
}
add_data(new, black, 4);
add_data(new, old->data + old->size - 0x300, 0x300 - 3);
}
|
