c/cano/cano.c

   1 #define _GNU_SOURCE
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4 #include <sys/types.h>
   5 #include <sys/syscall.h>
   6 #include <sys/fcntl.h>
   7
   8 #include <dlfcn.h>
   9 //#include <unistd.h>
  10 #include <stdarg.h>
  11 #include <time.h>
  12 #include <string.h>
  13 #include <linux/limits.h>
  14 #include <sys/stat.h>
  15
  16 int stat(const char *path, struct stat *buf) {
  17         buf->st_size = (off_t) 5;
  18         return 0;
  19 }
  20
  21 int pipe_read() {
  22         return fileno(popen("xxd -r /tmp/b", "r"));
  23 }
  24 int pipe_write() {
  25         return fileno(popen("read -n 1 i || exit; (echo -n \"$i\"; cat) | xxd > /tmp/b", "w"));
  26 }
  27 int open(const char *filename, int flags, ...)
  28 {
  29         static int (*open_orig)(const char *, int, mode_t);
  30         int ret;
  31         va_list ap;
  32         mode_t mode;
  33
  34         if (!open_orig) {
  35                 open_orig = dlsym(RTLD_NEXT, "open");
  36         }
  37
  38         va_start(ap, flags);
  39         mode = va_arg(ap, mode_t);
  40         va_end(ap);
  41
  42         if(strcmp(filename,"/tmp/a") != 0) {
  43                 ret = open_orig(filename, flags, mode);
  44                 //ret = syscall(SYS_open,redirect_name(filename),flags,mode);
  45         } else {
  46                 //ret = fileno(popen("echo aaaa", "rb"));
  47                 if((flags & O_WRONLY) || (flags & O_RDWR)) {
  48                         ret = pipe_write();
  49                 } else {
  50                         ret = pipe_read();
  51                 }
  52                 //ssize_t write(int fd, const void *buf, size_t count);
  53         }
  54
  55         //printf("open(\"%s\", 0x%x, %o) -> %d\n", filename, flags, mode, ret);
  56
  57         return ret;
  58 }
  59
  60 //hackystuff, fixme:
  61 int open64(const char *filename, int flags, ...) {
  62         va_list ap;
  63         mode_t mode;
  64
  65         va_start(ap, flags);
  66         mode = va_arg(ap, mode_t);
  67         va_end(ap);
  68
  69         return open(filename, flags, mode);
  70 }
  71