Re: Fw: [cobalt-users] C libraries for CGI

["support@xxxxxxxxxxx" <support@xxxxxxxxxxx>]

Mr. WebMost,

If you want to try it in c, here's one that compiles okay on a Raq2 with
just the standard libraries; no flames- I'm just posting it here so
everyone can see how easy it is. Errors? I didn't see any- if you use
this you're taking your OWN chances. I REPEAT, if you kill your own
machine/ core dump/ whatever, don't blame me- I offer this as one
possible example, could be and probably is buggy, of how it could be
done. Furthermore, I probably stole this from someone many years ago.

Now with that said, just save the folowing text (minus my signature of
course) as a text file called "something.c", upload it to your machine,
telnet in to the same directory you uploaded it to, and type "cc
something.c -o something.cgi". Then do an "ls -o" to make sure the new
file called "something.cgi" is set to be executable. Next create any
form that posts data to this cgi's url and watch the fun; hey, it works
for me!

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>

/*  C program example to parse data */

void closeup(int v)
{
   exit(v);
}

void dewebify(char *str)

{

   int x,y;

   for (x=0,y=0; str[y] != '\0'; x++,y++)
     switch (str[y]) {
      case '+':
	str[x] = ' ';
	break;
      case '%':
	str[y+1] = toupper(str[y+1]);
	str[y+2] = toupper(str[y+2]);
	if (str[y+1] >= 'A') str[x] = (str[y+1] - 'A' + 10) * 16;
	else str[x] = (str[y+1] - '0') * 16;
	if (str[y+2] >= 'A') str[x] += (str[y+2] - 'A' + 10);
	else str[x] += (str[y+2] - '0');
	y+=2;
	break;
      default:
	str[x] = str[y];
     }
   str[x]='\0';
}

int parse_input(char *name[], char *value[], int maxn)
{
   int length,c,i;
   char *line,*lstr;

   /* Get the size of the input */
   lstr = getenv("CONTENT_LENGTH");
   if (lstr == NULL) {
      printf("CONTENT_LENGTH environment variable is missing!\n");
      closeup(-1);
   }
   length = atoi(lstr);

   /* Allocate memory so we can read the data */
   line = (char *)malloc(length+1);
   if (line == NULL) {
      printf("Out of memory!\n");
      closeup(-1);
   }

   /* Read the data */
   if (read(0,line,length) < length) {
      printf("Error: Couldn't read input!\n");
      closeup(-1);
   }

   /* Break the data up into name=value strings. */

   for (c=0,name[c] = strtok(line,"&"); 
	name[c] != NULL && c < maxn;
	name[++c] = strtok(NULL,"&"));

    for (i=0; i< c; i++) {
      value[i] = strchr(name[i],'=');
      if (value[i] == NULL) {
	 printf("No '=' found in name/value pair\n");
	 closeup(-1);
      }
      *value[i] = '\0';
      value[i] = value[i]+1;
   }

   /* Clean up the remaining text.  */
   for (i=0; i<c; i++) {
      dewebify(name[i]);
      dewebify(value[i]);
   }

   /* Return the number of pairs read in */
   return c;
}

int main(int argc, char **argv, char **envp)
{
   int vcount,i;
   char *name[16],*value[16],*reqm;

   /* Tell the server and browser the kind of data we are sending*/
   printf("Content-type: text/html\n\n");

   printf("<TITLE>Parse CGI from C Example</TITLE>\n");
   printf("<center>\n<H1>Parse CGI from C Example<br>\n<hr></H1></center>\n");

   /* Parse the query string. */

   vcount = parse_input(name,value,16);

   /* Get the REQUEST_METHOD. */

   reqm = getenv("REQUEST_METHOD");
   if (reqm == NULL) {
      printf("Unkown REQUEST_METHOD\n");
      closeup(-1);
   }
   printf("Posted with the <b>%s</b> method<p>\n",reqm);

   printf("%d Name/Value Pairs:<p><pre>\n",vcount);

   /* Now print out the values */

   for (i=0;i<vcount;i++)
     printf("%10s:  %s\n",name[i],value[i]);

   printf("</pre>\n");

   closeup(0);

   /* You shouldn't ever get here */
   return 0;
}

 
-- 
Clayton McGow		        
support@xxxxxxxxxxx		
http://www.atoznet.com