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#include "builtins.h"
#include "shell.h"
#include <camellia/syscalls.h>
#include <errno.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
int main();
static int readline(char *buf, size_t max, FILE *f) {
char c = '\0';
size_t pos = 0;
while (pos < (max-1) && c != '\n' && fread(&c, 1, 1, f))
buf[pos++] = c;
buf[pos++] = '\0';
return pos;
}
static void execp(char **argv) {
if (!argv || !*argv) return;
if (argv[0][0] == '/') {
execv(argv[0], argv);
return;
}
size_t cmdlen = strlen(argv[0]);
char *s = malloc(cmdlen);
if (!s) {
printf("sh: out of memory.\n");
exit(1);
}
memcpy(s, "/bin/", 5);
memcpy(s + 5, argv[0], cmdlen + 1);
argv[0] = s;
execv(s, argv);
free(s);
}
static void run(char *cmd) {
#define ARGV_MAX 16
char *argv[ARGV_MAX];
char *redir;
int ret = parse(cmd, argv, ARGV_MAX, &redir);
if (ret < 0) {
printf("sh: error parsing command\n");
return;
}
if (!*argv) return;
/* "special" commands that can't be handled in a subprocess */
if (!strcmp(argv[0], "shadow")) {
// TODO process groups
_syscall_mount(-1, argv[1], strlen(argv[1]));
return;
} else if (!strcmp(argv[0], "exit")) {
exit(0);
}
if (fork()) {
_syscall_await();
return;
}
if (redir && !freopen(redir, "w", stdout)) {
// TODO stderr
exit(0);
}
if (!strcmp(argv[0], "echo")) {
printf("%s", argv[1]);
for (int i = 2; argv[i]; i++)
printf(" %s", argv[i]);
printf("\n");
} else if (!strcmp(argv[0], "fork")) {
main();
} else if (!strcmp(argv[0], "cat")) {
// TODO better argv handling
cmd_cat_ls(argv[1], false);
} else if (!strcmp(argv[0], "ls")) {
cmd_cat_ls(argv[1], true);
} else if (!strcmp(argv[0], "hexdump")) {
cmd_hexdump(argv[1]);
} else if (!strcmp(argv[0], "catall")) {
const char *files[] = {
"/init/fake.txt",
"/init/1.txt", "/init/2.txt",
"/init/dir/3.txt", NULL};
for (int i = 0; files[i]; i++) {
printf("%s:\n", files[i]);
cmd_cat_ls(files[i], false);
printf("\n");
}
} else if (!strcmp(argv[0], "touch")) {
cmd_touch(argv[1]);
} else {
execp(argv);
if (errno == EINVAL) {
printf("%s isn't a valid executable\n", argv[0]);
} else {
printf("unknown command: %s\n", argv[0]);
}
}
exit(0); /* kills the subprocess */
}
int main(int argc, char **argv) {
static char buf[256];
FILE *f = stdin;
if (argc > 1) {
f = fopen(argv[1], "r");
if (!f) {
printf("sh: couldn't open %s\n", argv[1]);
return 1;
}
}
for (;;) {
if (f == stdin)
printf("$ ");
readline(buf, 256, f);
if (feof(f)) return 0;
run(buf);
}
}
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