#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdarg.h>

#define _FCNTL_H
#include <bits/fcntl.h>
#undef _FCNTL_H

#ifdef __linux__
#include <sys/syscall.h>
#endif

#ifdef __GNUC__
extern char * program_invocation_name;
#endif

#define SYS_HEADER_PATH "/usr/include"
#define CONFIGURE_NAME "./configure"
#define SH_NAME "/bin/sh"

inline char * get_argv1(void);
inline char * get_argv1_linux(void);
int open64(const char *pathname, int flags, ...);

int open64(const char *pathname, int flags, ...) {
  int modes = 0;

  //  printf("Our name is: %s\n", program_invocation_name);
  if(! strncmp(program_invocation_name, SH_NAME, sizeof(SH_NAME) - 1)) {
    if(! strncmp(get_argv1(), CONFIGURE_NAME, sizeof(CONFIGURE_NAME) - 1)) {
      if(! strncmp(pathname, SYS_HEADER_PATH, sizeof(SYS_HEADER_PATH) - 1)) {
      //    execlp("apt-get", "install", );
      
      // 1) Check to see if header is in the database
      // 2) Fork if it's not, parent process waits on child
      // 3) Child execs process to grab and install the package
      // 4) Parent's wait unblocks and execution continues
      }
    }
  }
  if(flags & O_CREAT) {
    va_list list;
    
    va_start(list, flags);
    modes = va_arg(list, int);
    va_end(list);
	
    return syscall(SYS_open, pathname, flags, modes);
  }
  return syscall(SYS_open, pathname, flags);

      
}

inline char * get_argv1(void) {
#ifdef linux
  return get_argv1_linux();
#else
#error No method of retrieving the original command line has been implemented for this platform.
#endif
}

static char buf[256];
inline char * get_argv1_linux(void) {
  int rc;

  memset(buf, 0, sizeof(buf));
  snprintf(buf, sizeof(buf) - 1, "/proc/%i/cmdline", getpid());
  rc = syscall(SYS_open, &buf, O_RDONLY);
  if(rc == -1) {
#if 0
    fprintf(stderr, "*** INTERNAL BLDDEPS ERROR: could not retrieve original command line via\n"
	   "procfs.  If the proc filesystem is not mounted, then you can mount it\n"
	   "with this command:\n\n"
	   "# mount -t proc proc /proc");
    exit(1);
#endif /* 0 */ /* blddeps is probably not supposed to be that anal. */
    printf("Aiee!: %s\n", strerror(rc));
    return NULL;
  }

  // We're reusing the path buffer here for performance reasons
  read(rc, buf, sizeof(buf) - 1);
  buf[256] = '\0';
  return (strchr(buf, '\0') + 1);
  //  return buf;
}