/*                                                                   put.c   **    PUT CGI-SCRIPT   **   **    (c) COPYRIGHT INRIA/MIT/W3C 1996.   **    Please first read the full copyright statement in the file COPYRIGHT.   **   ** DISCLAIMER:   **   ** This is just an example script for handling PUT requests with the CERN   ** server. It's provided in an as-is basis, without any guarantee over its   ** functioning or any loss of data, accidental or intentional, coming    ** from its use. Users of this script are encouraged to fully review it   ** before integrating it into their systems.   **   ** This script has been compiled with gcc and tested with the CERN 3.0    ** HTTP server, running under Solaris 2.5 and Linux 2.0.0.   ** I tested the following clients against this server:   ** Amaya 0.9a, Netscape Gold 3.0, and AOLpress 1.2 beta.   ** Please email me if you use this script against/under something else.   **   ** You may find a link to the latest version of this script at:   **      http://www.w3.org/pub/WWW/Amaya/PutCern.html   **   ** HISTORY:   ** v0   20 May 96  Jose Kahan <kahan@w3.org>  Created from zero   ** v1.0 24 Dec 96  Jose Kahan                 Improved error detection   **                                            Added HTTP/1.x return codes */#include <stdio.h>#include <stdlib.h>#include <unistd.h>#include <string.h>#include <errno.h>#include <time.h>#include <fcntl.h>#include <signal.h>#include <sys/uio.h>#include <sys/types.h>#include <sys/stat.h>#define LF "\r\n"/***** HTTP status codes this script supports *****/#define OK         1  /* 200 */#define CREATED    2  /* 201 */#define UPDATED    3  /* 204 */#define ERROR     -1  /* 500 *//***** USER CONFIGURABLE OPTIONS *******//*** Here are some error status messages, in case you want to** customize them yourself*/#define INVALID_PATH_MSG       "Server did not give a valid URL path"#define INVALID_METHOD_MSG     "You must use a PUT method with this script"#define INVALID_CONTENT_LENGTH_MSG "Server did not send a correct Content-length"/*** Change the following flags  to specify which will be the Unix access rights of** the files that this script can create */#define FILE_RIGHTS S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH/*** Maximum number of bytes to read/write in a single operation */#define MAX_BUF_LEN  4048 /*** trace_on == 1 for a simple debug mode.** Turned off by default*/int trace_on = 0; /*** According to the HTTP/1.1 standard, there are at least two** different response status that a PUT command can give:** (201) when creating a new resource and (204) when updating** it. To find out the state of a resource, the script does an extra** system call. This wastes some time, and well, today's** browsers are satisfied with the 204 response. Thus, undefine** the following macro if you don't need this feature. */#define CREATE_UPDATE/***  define the following macro when running the script on a**  fully compliant HTTP/1.1 server. It'll activate**  the generation of a Location header to be sent together**  with an HTTP/1.1 201 response.*//**#define HTTP_11**//***** END OF USER CONFIGURABLE OPTIONS ******/extern char **environ;extern int errno;extern char *sys_errlist[];#if defined(__svr4__)#define CATCH_SIG#endif/***  Function Prototypes**  -------------------*/void trace (char *trace_msg);int copy_content (char *filename, long cl, char ** status_msg);void dump_result (char *url, char *status_msg, int status);static void SetSignal (void);/* ------------------------------------------------------------------------- *//***  trace**  -----**  Prints error messages --- for debugging*/voidtrace (char *trace_msg){  if (trace_on)    fprintf (stderr, "PUT TRACE: %s\n", trace_msg);}/***  dump_result**  -----------**  Outputs the PUT result thru  stdout, according to the CGI**  specification.*/voiddump_result (char *url, char *status_msg, int status){  switch(status) {  case OK:    /* not used for the moment, but it does not hurt to have this case       here */    printf ("Status: 200%s", LF);    printf ("Content-Type: text/html%s%s", LF, LF);    printf ("<HTML><HEAD><TITLE>PUT success</TITLE></HEAD>%s"            "<BODY><P>Created the following resource:<CODE>%s</CODE>"	    "</P>%s</BODY></HTML>",LF,LF,url);    break;  case UPDATED:    trace ("Updating a file");    printf ("Status: 204%s%s", LF, LF);     break;  case CREATED:    trace ("Creating a file");    printf ("Status: 201%s%s", LF, LF);#ifdef HTTP_11    /*    printf ("Location:%s%s", url, LF);*/    printf ("Content-Type: text/html%s%s", LF, LF);    printf ("<HTML><HEAD><TITLE>PUT success</TITLE></HEAD>%s"            "<BODY><P>Created the following resource:</P><P><CODE>%s</CODE>"	    "</P>%s</BODY></HTML>",LF, LF, url);#endif /* HTTP/1.1 */    break;    case ERROR:  default:    trace ("Uh oh, an error ...");    printf ("Status: 500 cgi PUT script error%s", LF);    printf ("Content-Type: text/html%s%s",LF,LF);     printf ("<HTML><HEAD><TITLE>cgi PUT script error</TITLE></HEAD>\n");    if(url && url[0] != '\0')      printf("<BODY><P>Could not save the following URL:</P><P><CODE>%s</CODE></P>\n", url);    else      printf("<BODY><P>Could not save the URL</P>\n");    if(status_msg && status_msg[0] != '\0')      printf("<P>Reason: <CODE>%s</CODE></P>\n", status_msg);  printf("</BODY></HTML>");  break;  } /* switch */}/***  SetSignal**  ---------**  This function sets up signal handlers. This might not be necessary to**  call if the application has its own handlers.*/static voidSetSignal (void){  /* On some systems (SYSV) it is necessary to catch the SIGPIPE signal  ** when attemting to connect to a remote host where you normally should  ** get `connection refused' back  */  if (signal (SIGPIPE, SIG_IGN) == SIG_ERR)	trace("HTSignal.... Can't catch SIGPIPE");  else	trace("HTSignal.... Ignoring SIGPIPE");}/***  copy_content**  ------------**  Creates a filename and then copies cl bytes from stdin into it **  If there's an error, it returns ERROR and sets status_msg to**  the corresponding Unix system error message. Otherwise, it**  returns either CREATED or UPDATED, depending whether the file**  already existed or not. */ intcopy_content (char *filename, long cl, char **status_msg){  char buffer[MAX_BUF_LEN];  int fd_out;  int nb_elements_read, nb_elements_write;  int buf_len;  int status;  /*  ** this is for verifying if the file already existed, to be compliant  ** with HTTP/1.1.   */#ifdef CREATE_UPDATE  if((fd_out = open (filename, O_EXCL | O_WRONLY | O_CREAT | O_TRUNC, FILE_RIGHTS)) == -1) {    if (errno == EEXIST) {      trace("File existed !");      status = UPDATED;      if ((fd_out = creat (filename, FILE_RIGHTS)) == -1) {	*status_msg = sys_errlist[errno];	trace (*status_msg);	return (ERROR);      }    }    else {      *status_msg = sys_errlist[errno];      trace (*status_msg);      return(ERROR);    }  } else    status = CREATED;#else  if ((fd_out = creat (filename, FILE_RIGHTS)) == -1) {    *status_msg = sys_errlist[errno];    trace (*status_msg);    return (ERROR);  }  else     status = CREATED;#endif /* CREATE_UPDATE */   buf_len = MAX_BUF_LEN;  while (status != ERROR && cl) {    if (cl < buf_len)	buf_len = cl;    nb_elements_read = read (0, buffer, buf_len);    if (nb_elements_read == -1) {      *status_msg = sys_errlist[errno];      trace (*status_msg);      status = ERROR;      break;    }     nb_elements_write = write (fd_out, buffer, nb_elements_read);    if (nb_elements_write == -1 || nb_elements_write != nb_elements_read) {      *status_msg = sys_errlist[errno];      trace (*status_msg);      status = ERROR;      break;    }    cl = cl - nb_elements_read;  }  if (close (fd_out) == -1) {    *status_msg = sys_errlist[errno];    trace (*status_msg);    status = ERROR;  }  return (status);}        /***  main**  ----**  Does not receives any direct input parameters. They come from**  the Unix environment variables, according to the**  CGI specification.*/intmain (int argc, char *argv[]){  char *filename;  char *method;  char *url;  char *status_msg;  char *pcl;  long cl;  int status;  trace ("I\'m alive (PUT)");#ifdef CATCH_SIG   SetSignal ();#endif  /*  ** Read and control the CGI environment variables  */  trace ("Reading CGI environment variables");  method = getenv ("REQUEST_METHOD");  url = getenv ("PATH_INFO");  filename = getenv ("PATH_TRANSLATED");  pcl = getenv ("CONTENT_LENGTH");  if(!url || !url[0] || !filename || !filename[0]) {    status = ERROR;    status_msg = INVALID_PATH_MSG;    url = NULL;    trace(status_msg);  }  else if (!method || strcmp(method, "PUT")) {    status = ERROR;    status_msg = INVALID_METHOD_MSG;    trace(status_msg);  }  else if (!pcl || !pcl[0]) {    status = ERROR;    status_msg = INVALID_CONTENT_LENGTH_MSG;    trace(status_msg);  }  else {    if(trace_on)      fprintf (stderr, "REQUEST_METHOD = %s\n"	               "PATH_INFO = %s\n"	               "PATH_TRANSLATED = %s\n"	               "CONTENT_LENGTH = %s\n",	                method, url, filename, pcl);    /* set the number of bytes ( content length) to read */    cl = atol (pcl);    /*     **try to save the file    */    status = copy_content(filename, cl, &status_msg);  } /* if-else */  if(trace_on)    fprintf(stderr,"status is %d\n", status);  dump_result (url, status_msg, status);  exit(0); }/*** end of module put.c*/