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
|
#include <stdint.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <err.h>
#include <sys/stat.h>
#include <string.h>
#define ANSI_FG_RED "\033[0;31m"
#define ANSI_FG_DEFAULT "\033[0;39m"
int main(int argc, char **argv)
{
for (int i = 1; i < argc; i++)
{
struct stat fileinfo;
if (stat(argv[i], &fileinfo))
err(-1, "couldn't stat " ANSI_FG_RED "%s" ANSI_FG_DEFAULT,
argv[i]);
if (!S_ISREG(fileinfo.st_mode))
errx(-1, ANSI_FG_RED "%s" ANSI_FG_DEFAULT
" is not a regular file.", argv[i]);
if (fileinfo.st_size > UINT32_MAX)
errx(-1, ANSI_FG_RED "%s" ANSI_FG_DEFAULT
" is too big.", argv[i]);
uint32_t file_size = fileinfo.st_size;
uint32_t name_size = strlen(argv[i]);
if (fwrite(&name_size, 4, 1, stdout) != 1)
errx(-1, "error writing to stdout");
if (printf("%s", argv[i]) != name_size)
errx(-1, "error writing to stdout");
for (int j = 0; (j + (name_size & 0b11)) & 0b11; j++)
if (putchar('\0'))
errx(-1, "error writing to stdout");
if (fwrite(&file_size, 4, 1, stdout) != 1)
errx(-1, "error writing to stdout");
if (fflush(stdout))
err(-1, "couldn't flush stdout");
pid_t pid;
int wstatus;
switch (pid = fork())
{
case -1:
err(-1, "couldn't fork");
case 0:
if (execlp("cat", "cat", argv[i], NULL))
err(-1, "couldn't execute cat");
default:
if (wait(&wstatus) == -1)
err(-1, "error waiting for child");
if (!WIFEXITED(wstatus) || WEXITSTATUS(wstatus))
exit(-1);
}
for (int j = 0; (j + (file_size & 0b11)) & 0b11; j++)
if (putchar('\0'))
errx(-1, "error writing to stdout");
}
return 0;
}
|
