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/* http.c */
#include "elvis.h"
#ifdef PROTOCOL_HTTP
static sockbuf_t *sb;
/* Open an HTTP resource for reading. Returns True if successful, or False
* for error (after giving an error message).
*/
BOOLEAN httpopen(site_port, resource)
char *site_port; /* host name and optional port number */
char *resource; /* name of file at remote host */
{
char *line, *p;
/* Open a connection to the server */
sb = netconnect(site_port, 80);
if (!sb)
{
/* error message already given */
return False;
}
/* Send the "GET" request to the HTTP server. Note that netputline()
* will add a second CRLF pair after the "HTTP/1.0" string. This is
* important, because when an HTTP server sees "HTTP/1.0" it expects
* suplemental information to appear on following lines, up to the
* next blank line. It won't process the request until it sees that
* blank line.
*/
msg(MSG_STATUS, "[s]requesting $1", resource);
if (!netputline(sb, "GET", resource, "HTTP/1.0\r\n"))
{
/* error message already given */
return False;
}
/* Success, so far. Now ready to begin reading data. */
msg(MSG_STATUS, "receiving...");
/* Fill the receive buffer. */
if (!netread(sb))
return False;
/* If the response starts with "HTTP", then assume it is in MIME
* format. Skip the header, and watch for a "Content-Length:" line.
*/
if (netbytes(sb) >= 4 && !strncmp(netbuffer(sb), "HTTP", 4))
{
while ((line = netgetline(sb)) != NULL && *line)
{
/* Convert the header label to lowercase */
for (p = line; *p && *p != ':'; p++)
{
*p = tolower(*p);
}
/* If "Content-Length:" then allow url.c to display
* the size.
*/
if (!strncmp(line, "content-length: ", 16))
{
urlbytes(atol(&line[16]));
}
}
}
return True;
}
/* Read some data from the remote server */
int httpread(buf, nbytes)
CHAR *buf;
int nbytes;
{
/* try to fill sb's buffer */
if (sb->left > 0 && !netread(sb))
return -1;
/* never read more data than there is in sb's buffer */
if (netbytes(sb) < nbytes)
nbytes = netbytes(sb);
/* copy bytes from sb's buffer to buf */
if (nbytes > 0)
{
memcpy(buf, netbuffer(sb), nbytes);
netconsume(sb, nbytes);
}
return nbytes;
}
/* close the socket */
void httpclose P_((void))
{
netdisconnect(sb);
}
#endif /* PROTOCOL_HTTP */
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