#include <stdio.h>
#include <fcntl.h>
#include <dlfcn.h>
#include <sys/types.h>
#include <sys/syscall.h>
#include <unistd.h>
#include <errno.h>
#include "libload.h"

char *fnames[] = {
	"open",
	"open64",
	"read",
	"write",
	"close",
	"lseek",
	"dup",
	"dup2",
	"readv",
	"writev",
	"fcntl",
	"fork",
	"pread",
	"pwrite",
	"fdopen",
	"fopen",
	"fopen64",
	"fclose",
	"fread",
	"fwrite",
	"fseek",
	/*	"fseek64", */
	"rewind",
	"fsetpos",
	"creat",
	"creat64",
	"fgetc",
	"fgets",
	"getc",
	"gets",
	"fputc",
	"fputs",
	"putc",
	"puts",
	"ungetc",
	"vfscanf",
	"fscanf",
	"vfprintf",
	"fprintf",
	"socket",
	"accept",
	"send",
	"sendto",
	"sendmsg",
	"recv",
	"recvfrom",
	"recvmsg",
	"execve",
	"execl",
	"execlp",
	"execle",
	"execv",
	"execvp"
};

void *farray[sizeof fnames / sizeof (char *)];

extern int errno;
/* Needed because all normal I/O calls are trapped, but not yet loaded */
void emergency_perror(char *c) {
	char buf[256], *p;

	p = strerror(errno);
	snprintf(buf, sizeof buf, "%s:%s\n", p, c);
	if (syscall(SYS_write, 2, buf, strlen(buf)) < 0)
		exit(1);
}

int libload() {
	int i;
	void *dlp;

	if ( ((dlp = dlopen("libc.so.6", RTLD_NOW | RTLD_GLOBAL)) 
	     == NULL) && (dlp = dlopen("libc.so.6.1", RTLD_NOW | RTLD_GLOBAL)) == NULL)  {
		emergency_perror("Failed to open libc in libload");
		exit(ENOTSUP);
	}
	for (i = 0; i < sizeof fnames / sizeof (char *); i++) {
		if ( (farray[i] = dlsym(dlp, fnames[i])) == NULL) {
			emergency_perror("dlsym failure in libload");
			fprintf(stderr, "Failed to get symbol %s, index %d\n",
				fnames[i], i);
			exit(1);
		}
	}
	return 0;
}