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#include "builtins.h"
#include <stdio.h>
#include <string.h>
#include <unistd.h>
void cmd_cat_ls(const char *args, bool ls) {
FILE *file;
static char buf[512];
int len; // first used for strlen(args), then length of buffer
if (args) {
len = strlen(args);
memcpy(buf, args, len + 1); // no overflow check - the shell is just a PoC
if (ls) { // paths to directories always have a trailing slash
if (buf[len-1] != '/') {
buf[len] = '/';
buf[len+1] = '\0';
}
}
file = fopen(buf, "r");
} else if (ls) { /* ls default argument */
file = fopen("/", "r");
} else { /* cat default argument */
file = file_clone(stdin);
}
if (!file) {
printf("couldn't open.\n");
return;
}
while (!feof(file)) {
int len = fread(buf, 1, sizeof buf, file);
if (len <= 0) break;
if (ls) {
for (int i = 0; i < len; i++)
if (buf[i] == '\0') buf[i] = '\n';
}
fwrite(buf, 1, len, stdout);
}
fclose(file);
}
void cmd_hexdump(const char *args) {
static uint8_t buf[512];
int fd, len;
fd = _syscall_open(args, strlen(args), 0);
if (fd < 0) {
printf("couldn't open.\n");
return;
}
len = _syscall_read(fd, buf, sizeof buf, 0);
for (int i = 0; i < len; i += 16) {
printf("%08x ", i);
for (int j = i; j < i + 8 && j < len; j++)
printf("%02x ", buf[j]);
printf(" ");
for (int j = i + 8; j < i + 16 && j < len; j++)
printf("%02x ", buf[j]);
printf(" |");
for (int j = i; j < i + 16 && j < len; j++) {
char c = '.';
if (0x20 <= buf[j] && buf[j] < 0x7f) c = buf[j];
printf("%c", c);
}
printf("|\n");
}
close(fd);
}
void cmd_touch(const char *args) {
int fd = _syscall_open(args, strlen(args), OPEN_CREATE);
if (fd < 0) {
printf("couldn't create file.\n");
return;
}
close(fd);
}
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