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#include "builtins.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 bool isspace(char c) {
return c == ' ' || c == '\t' || c == '\n';
}
static char *strsplit(char *base, char delim) {
if (!base) return NULL;
while (*base) {
if (delim ? *base == delim : isspace(*base)) {
*base++ = '\0';
return base;
}
base++;
}
return NULL;
}
static char *strtrim(char *s) {
char *end;
if (!s) return NULL;
while (isspace(*s)) s++;
end = s + strlen(s);
while (end > s && isspace(end[-1])) end--;
*end = '\0';
return s;
}
// TODO fgets
static int readline(char *buf, size_t max) {
char c = '\0';
size_t pos = 0;
while (pos < (max-1) && c != '\n' && fread(&c, 1, 1, stdin))
buf[pos++] = c;
buf[pos++] = '\0';
return pos;
}
static void execp(const char *cmd) {
if (*cmd == '/') {
execv(cmd, NULL);
return;
}
size_t cmdlen = strlen(cmd);
char *s = malloc(cmdlen);
if (!s) {
printf("sh: out of memory.\n");
exit(1);
}
memcpy(s, "/bin/", 5);
memcpy(s + 5, cmd, cmdlen + 1);
char *argv[] = {(char*)cmd, NULL};
execv(s, argv);
free(s);
}
static void run(char *cmd) {
char *args, *redir;
cmd = strtrim(cmd);
if (!*cmd) return;
redir = strtrim(strsplit(cmd, '>'));
cmd = strtrim(cmd);
args = strtrim(strsplit(cmd, 0));
/* "special" commands that can't be handled in a subprocess */
if (!strcmp(cmd, "shadow")) {
// TODO process groups
_syscall_mount(-1, args, strlen(args));
return;
} else if (!strcmp(cmd, "exit")) {
exit(0);
}
if (fork()) {
_syscall_await();
return;
}
if (redir && !freopen(redir, "w", stdout)) {
// TODO stderr
exit(0);
}
if (!strcmp(cmd, "echo")) {
printf("%s\n", args);
} else if (!strcmp(cmd, "fork")) {
main();
} else if (!strcmp(cmd, "cat")) {
cmd_cat_ls(args, false);
} else if (!strcmp(cmd, "ls")) {
cmd_cat_ls(args, true);
} else if (!strcmp(cmd, "hexdump")) {
cmd_hexdump(args);
} else if (!strcmp(cmd, "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(cmd, "touch")) {
cmd_touch(args);
} else {
execp(cmd);
if (errno == EINVAL) {
printf("%s isn't a valid executable\n", cmd);
} else {
printf("unknown command: %s\n", cmd);
}
}
exit(0); /* kills the subprocess */
}
int main(void) {
static char buf[256];
for (;;) {
printf("$ ");
readline(buf, 256);
if (feof(stdin)) return 0;
run(buf);
}
}
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