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/*
** This file contains code to fetch a single URL into a local file.
*/
#include <stdio.h>
#include <netdb.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <linux/in.h>
#include "httpget.h"
#define strnicmp strncasecmp
/*
** Get a URL using HTTP. Return the result code. If a Location: field
** appears in the header, write it into zLocation[]. Location[] should
** be at least 200 characters in size.
*/
static int
HttpTryOnce(char *zUrl, char *zLocalFile, int quiet, char *zLocation){
int i, j;
int nErr = 0; /* Number of errors */
char *zPath; /* Pathname to send as second argument to GET */
int iPort; /* TCP port for the server */
struct hostent *pHost; /* Name information */
int s; /* The main communications socket */
int c; /* A character read from the remote side */
int n; /* Number of characters in header */
int rc = 200; /* The result code */
FILE *sock; /* FILE corresponding to file descriptor s */
FILE *out; /* Write output here */
int last_was_nl; /* TRUE if last character received was '\n' */
struct sockaddr_in addr; /* The address structure */
int nByte = 0;
char zIpAddr[400]; /* The IP address of the server to print */
char zMsg[1000]; /* Space to hold error messages */
char zLine[1000]; /* A single line of the header */
out = fopen(zLocalFile, "w");
if( out==0 ){
sprintf(zMsg, "can't open output fule \"%.100s\"", zLocalFile);
perror(zMsg);
return 1;
}
i = 0;
if( strnicmp(zUrl,"http:",5)==0 ){ i = 5; }
while( zUrl[i]=='/' ){ i++; }
j = 0;
while( zUrl[i] && zUrl[i]!=':' && zUrl[i]!='/' ){
if( j<sizeof(zIpAddr)-1 ){ zIpAddr[j++] = zUrl[i]; }
i++;
}
zIpAddr[j] = 0;
if( zUrl[i]==':' ){
iPort = 0;
i++;
while( isdigit(zUrl[i]) ){
iPort = iPort*10 + zUrl[i] - '0';
i++;
}
}else{
iPort = 80;
}
zPath = &zUrl[i];
addr.sin_family = AF_INET;
addr.sin_port = htons(iPort);
*(int*)&addr.sin_addr = inet_addr(zIpAddr);
if( -1 == *(int*)&addr.sin_addr ){
pHost = gethostbyname(zIpAddr);
if( pHost==0 ){
fprintf(stderr,"can't resolve host name: %s\n",zIpAddr);
return 1;
}
memcpy(&addr.sin_addr,pHost->h_addr_list[0],pHost->h_length);
if( !quiet ){
fprintf(stderr,"Address resolution: %s -> %d.%d.%d.%d\n",zIpAddr,
pHost->h_addr_list[0][0]&0xff,
pHost->h_addr_list[0][1]&0xff,
pHost->h_addr_list[0][2]&0xff,
pHost->h_addr_list[0][3]&0xff);
}
}
s = socket(AF_INET,SOCK_STREAM,0);
if( s<0 ){
sprintf(zMsg,"can't open socket to %.100s", zIpAddr);
perror(zMsg);
fclose(out);
return 1;
}
if( connect(s,(struct sockaddr*)&addr,sizeof(addr))<0 ){
sprintf(zMsg,"can't connect to host %.100s", zIpAddr);
perror(zMsg);
fclose(out);
return 1;
}
sock = fdopen(s,"r+");
if( *zPath==0 ) zPath = "/";
fprintf(sock,"GET %s HTTP/1.0\r\n",zPath);
fprintf(sock,"User-Agent: Mozilla/2.0 (X11; U; Linux 0.99p17 i486)\r\n");
if( iPort!=80 ){
fprintf(sock,"Host: %s:%d\r\n", zIpAddr, iPort);
}else{
fprintf(sock,"Host: %s\r\n", zIpAddr);
}
fprintf(sock,"Accept: image/gif, image/x-xbitmap, image/jpeg, */*\r\n");
fprintf(sock,"\r\n");
fflush(sock);
n = 0;
rc = 0;
while( (c=getc(sock))!=EOF && (c!='\n' || !last_was_nl) ){
if( c=='\r' ) continue;
last_was_nl = (c=='\n');
if( last_was_nl ){
zLine[n] = 0;
if( strncmp(zLine,"Location:",9)==0 && zLocation ){
int j, k;
for(j=9; isspace(zLine[j]); j++){}
k = 0;
while( zLine[j] && !isspace(zLine[j]) && k<199 ){
zLocation[k++] = zLine[j++];
}
zLocation[k] = 0;
if( !quiet ) fprintf(stderr,"Location: %s\n", zLocation);
}else if( rc==0 ){
sscanf(zLine,"HTTP/%*d.%*d %d ",&rc);
if( !quiet ) fprintf(stderr,"Status: %d\n", rc);
}
}
if( n<sizeof(zLine)-1 ){ zLine[n++] = c; }
if( last_was_nl ){ n = 0; }
}
if( rc==0 ) rc = 200;
if( !quiet ){
fprintf(stderr, "Reading %s...", zUrl);
}
while( (c=getc(sock))!=EOF ){
nByte++;
putc(c,out);
}
if( !quiet ){
fprintf(stderr, " %d bytes\n", nByte);
}
fclose(sock);
fclose(out);
return rc;
}
/*
** Get the file. Take up to 7 redirects.
*/
int HttpFetch(
char *zUrl, /* Fetch this URL */
char *zLocalFile, /* Write to this file */
int quiet, /* Be quiet if true */
int nActual, /* Size of zActual[] */
char *zActual /* Write actual URL retrieved here */
){
int i;
int rc;
char *zOriginalUrl = zUrl;
char zLocation[300];
for(i=0; i<7; i++){
if( !quiet ) fprintf(stderr,"HTTP: %s -> %s\n", zUrl, zLocalFile);
rc = HttpTryOnce(zUrl, zLocalFile, quiet, zLocation);
if( rc==301 || rc==302 ){
char *z;
const char *az[2];
az[0] = zLocation;
az[1] = 0;
z = ResolveUrl(zUrl, az);
if( zUrl!=zOriginalUrl ){
free(zUrl);
}
zUrl = z;
}else{
break;
}
}
if( nActual>0 && zActual!=0 ){
sprintf(zActual, "%.*s", nActual, zUrl);
}
if( zUrl!=zOriginalUrl ){
free(zUrl);
}
return rc;
}
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