/*
 * Correctness-test pnminsdel.
 *
 * Runs pnminsdel repeatedly, with randomly-chosen arguments and input
 *  data, checking that the output is what it should be.
 *
 * Each run randomly chooses:
 *
 *	* Size of input, each coordinate random in [8..16]
 *	* Input pixels are random
 *	* 0 to 15 command-line args
 *	* Each command-line arg is, randomly,
 *	  * X or Y axis
 *	  * Insert [1..8] pixels of random value, at random location
 *	  * Delete [1..size-1] pixels at random location
 *	    (deletes are suppressed if size is 1)
 *
 * The correct output is computed by copying pixels around in an array;
 *  the actual output is compared with this.
 */

#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdarg.h>
#include <strings.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <sys/socket.h>

extern const char *__progname;

static unsigned char image[256][256];
static int image_x;
static int image_y;
static unsigned char input[16][16];
static int input_x;
static int input_y;
static int testpass;

static void init(void)
{
 srandom(time(0));
 testpass = 0;
}

static void test_case(void)
{
 int x;
 int y;
 int a;
 int e;
 int i;
 int c;
 int ip[2];
 int op[2];
 int xp[2];
 pid_t tkid;
 pid_t ikid;
 pid_t kid;
 int status;
 char *subargs[64];
 int nsubargs;
 FILE *f;
 char *hdr;

 auto void add_arg(const char *, ...)
	__attribute__((__format__(__printf__,1,2)));
 auto void add_arg(const char *fmt, ...)
  { va_list ap;
    va_start(ap,fmt);
    vasprintf(&subargs[nsubargs],fmt,ap);
    va_end(ap);
    nsubargs ++;
  }

 auto void fail(const char *, ...)
	__attribute__((__format__(__printf__,1,2),__noreturn__));
 auto void fail(const char *fmt, ...)
  { int i;
    int x;
    int y;
    va_list ap;
    fprintf(stderr,"%s: failure: ",__progname);
    va_start(ap,fmt);
    vfprintf(stderr,fmt,ap);
    va_end(ap);
    fprintf(stderr,"\narglist:");
    for (i=0;subargs[i];i++) fprintf(stderr," %s",subargs[i]);
    fprintf(stderr,"\ninput image:\nP2\n%d %d\n255\n",input_x,input_y);
    for (y=0;y<input_y;y++)
     { for (x=0;x<input_x;x++)
	{ fprintf(stderr," %d",input[x][y]);
	}
       fprintf(stderr,"\n");
     }
    fprintf(stderr,"expected out image:\nP2\n%d %d\n255\n",image_x,image_y);
    for (y=0;y<image_y;y++)
     { for (x=0;x<image_x;x++)
	{ fprintf(stderr," %d",image[x][y]);
	}
       fprintf(stderr,"\n");
     }
    exit(1);
  }

 input_x = 8 + (random() % 9);
 input_y = 8 + (random() % 9);
 image_x = input_x;
 image_y = input_y;
 for (y=input_y-1;y>=0;y--) for (x=input_x-1;x>=0;x--)
  { input[x][y] = random() & 0xff;
    image[x][y] = input[x][y];
  }
 nsubargs = 0;
 add_arg("pnminsdel");
 for (a=15;a>0;a--)
  { if (random() % 3)
     { if (random() % 3)
	{ char axis;
	  int n;
	  int loc;
	  int v;
	  axis = (random() & 1) ? 'y' : 'x';
	  n = 1 + (random() % 8);
	  loc = random() % (1 + ((axis=='x') ? image_x : image_y));
	  v = random() & 0xff;
	  add_arg("ins%c",axis);
	  add_arg("%d@%d",n,loc);
	  add_arg("%d",v);
	  switch (axis)
	   { case 'x':
		for (y=image_y-1;y>=0;y--) for (x=image_x-1;x>=0;x--)
		 { if (x >= loc) image[x+n][y] = image[x][y];
		 }
		for (y=image_y-1;y>=0;y--) for (x=n-1;x>=0;x--)
		 { image[loc+x][y] = v;
		 }
		image_x += n;
		break;
	     case 'y':
		for (y=image_y-1;y>=0;y--) for (x=image_x-1;x>=0;x--)
		 { if (y >= loc) image[x][y+n] = image[x][y];
		 }
		for (y=n-1;y>=0;y--) for (x=image_x-1;x>=0;x--)
		 { image[x][loc+y] = v;
		 }
		image_y += n;
		break;
	     default:
		abort();
		break;
	   }
	}
       else
	{ char axis;
	  int n;
	  int d;
	  int loc;
	  axis = (random() & 1) ? 'y' : 'x';
	  d = (axis == 'x') ? image_x : image_y;
	  if (d < 2) continue;
	  n = (random() % (d-1)) + 1;
	  loc = random() % (d - n + 1);
	  add_arg("del%c",axis);
	  add_arg("%d@%d",n,loc);
	  switch (axis)
	   { case 'x':
		for (y=0;y<image_y;y++) for (x=0;x<image_x;x++)
		 { if (x >= n+loc) image[x-n][y] = image[x][y];
		 }
		image_x -= n;
		break;
	     case 'y':
		for (y=0;y<image_y;y++) for (x=0;x<image_x;x++)
		 { if (y >= n+loc) image[x][y-n] = image[x][y];
		 }
		image_y -= n;
		break;
	     default:
		abort();
		break;
	   }
	}
     }
  }
 subargs[nsubargs] = 0;
 if ((pipe(&ip[0]) < 0) || (pipe(&op[0]) < 0))
  { fprintf(stderr,"%s: pipe: %s\n",__progname,strerror(errno));
    exit(1);
  }
 if (socketpair(AF_LOCAL,SOCK_STREAM,0,&xp[0]) < 0)
  { fprintf(stderr,"%s: socketpair: %s\n",__progname,strerror(errno));
    exit(1);
  }
 tkid = fork();
 if (tkid < 0)
  { fprintf(stderr,"%s: fork: %s\n",__progname,strerror(errno));
    exit(1);
  }
 if (tkid == 0)
  { close(ip[1]);
    close(op[0]);
    if (ip[0] != 0)
     { dup2(ip[0],0);
       close(ip[0]);
     }
    if (op[1] != 1)
     { dup2(op[1],1);
       close(op[1]);
     }
    close(xp[0]);
    fcntl(xp[1],F_SETFD,1);
    execv("pnminsdel",&subargs[0]);
    e = errno;
    write(xp[1],&e,sizeof(int));
    exit(1);
  }
 close(xp[0]);
 close(ip[0]);
 close(op[1]);
 i = recv(xp[1],&e,sizeof(e),MSG_WAITALL);
 if (i == sizeof(e))
  { fprintf(stderr,"%s: exec pnminsdel: %s\n",__progname,strerror(e));
    exit(1);
  }
 if (i != 0)
  { fprintf(stderr,"%s: bizarre exec pipe error: got %d not %d\n",__progname,i,(int)sizeof(e));
    exit(1);
  }
 close(xp[1]);
 ikid = fork();
 if (ikid < 0)
  { fprintf(stderr,"%s: fork: %s\n",__progname,strerror(errno));
    exit(1);
  }
 if (ikid == 0)
  { close(op[0]);
    f = fdopen(ip[1],"w");
    fprintf(f,"P5\n%d %d\n255\n",input_x,input_y);
    for (y=0;y<input_y;y++) for (x=0;x<input_x;x++) putc(input[x][y],f);
    fflush(f);
    exit(0);
  }
 close(ip[1]);
 f = fdopen(op[0],"r");
 asprintf(&hdr,"P5\n%d %d\n255\n",image_x,image_y);
 for (i=0;hdr[i];i++)
  { c = getc(f);
    if (c == EOF) fail("EOF reading header (after %d)",i);
    if (c != hdr[i]) fail("header wrong (%02x, not %02x, after %d)",(unsigned char)c,hdr[i],i);
  }
 for (y=0;y<image_y;y++) for (x=0;x<image_x;x++)
  { c = getc(f);
    if (c == EOF) fail("EOF looking for pixel (%d,%d)",x,y);
    if (c != image[x][y]) fail("pixel (%d,%d) wrong (%d, not %d)",x,y,c,image[x][y]);
  }
 c = getc(f);
 if (c != EOF) fail("junk after end of picture");
 fclose(f);
 while ((ikid >= 0) || (tkid >= 0))
  { kid = wait(&status);
    if (kid < 0)
     { fprintf(stderr,"%s: wait: %s\n",__progname,strerror(errno));
       exit(1);
     }
    if (kid == ikid)
     { ikid = -1;
       continue;
     }
    if (kid == tkid)
     { tkid = -1;
       if (WIFEXITED(status))
	{ if (WEXITSTATUS(status))
	   { fail("exit %d",WEXITSTATUS(status));
	   }
	}
       else if (WIFSIGNALED(status))
	{ fail("signal %d%s",WTERMSIG(status),WCOREDUMP(status)?" (core dumped)":"");
	}
       continue;
     }
    fprintf(stderr,"%s: unknown child %d died\n",__progname,(int)kid);
  }
 while (nsubargs > 0) free(subargs[--nsubargs]);
 testpass ++;
 if ((testpass % 1000) == 0)
  { printf("%d\n",testpass);
    fflush(stdout);
  }
}

int main(void);
int main(void)
{
 init();
 while (1) test_case();
}