/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/*
* Author: Wan-Teh Chang
*
* Given an HTTP URL, httpget uses the GET method to fetch the file.
* The fetched file is written to stdout by default, or can be
* saved in an output file.
*
* This is a single-threaded program.
*/
#include "prio.h"
#include "prnetdb.h"
#include "prlog.h"
#include "prerror.h"
#include "prprf.h"
#include "prinit.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h> /* for atoi */
#define FCOPY_BUFFER_SIZE (16 * 1024)
#define INPUT_BUFFER_SIZE 1024
#define LINE_SIZE 512
#define HOST_SIZE 256
#define PORT_SIZE 32
#define PATH_SIZE 512
/*
* A buffer for storing the excess input data for ReadLine.
* The data in the buffer starts from (including) the element pointed to
* by inputHead, and ends just before (not including) the element pointed
* to by inputTail. The buffer is empty if inputHead == inputTail.
*/
static char inputBuf[INPUT_BUFFER_SIZE];
/*
* inputBufEnd points just past the end of inputBuf
*/
static char *inputBufEnd = inputBuf + sizeof(inputBuf);
static char *inputHead = inputBuf;
static char *inputTail = inputBuf;
static PRBool endOfStream = PR_FALSE;
/*
* ReadLine --
*
* Read in a line of text, terminated by CRLF or LF, from fd into buf.
* The terminating CRLF or LF is included (always as '\n'). The text
* in buf is terminated by a null byte. The excess bytes are stored in
* inputBuf for use in the next ReadLine call or FetchFile call.
* Returns the number of bytes in buf. 0 means end of stream. Returns
* -1 if read fails.
*/
PRInt32 ReadLine(PRFileDesc *fd, char *buf, PRUint32 bufSize)
{
char *dst = buf;
char *bufEnd = buf + bufSize; /* just past the end of buf */
PRBool lineFound = PR_FALSE;
char *crPtr = NULL; /* points to the CR ('\r') character */
PRInt32 nRead;
loop:
PR_ASSERT(inputBuf <= inputHead && inputHead <= inputTail
&& inputTail <= inputBufEnd);
while (lineFound == PR_FALSE && inputHead != inputTail
&& dst < bufEnd - 1) {
if (*inputHead == '\r') {
crPtr = dst;
} else if (*inputHead == '\n') {
lineFound = PR_TRUE;
if (crPtr == dst - 1) {
dst--;
}
}
*(dst++) = *(inputHead++);
}
if (lineFound == PR_TRUE || dst == bufEnd - 1 || endOfStream == PR_TRUE) {
*dst = '\0';
return dst - buf;
}
/*
* The input buffer should be empty now
*/
PR_ASSERT(inputHead == inputTail);
nRead = PR_Read(fd, inputBuf, sizeof(inputBuf));
if (nRead == -1) {
*dst = '\0';
return -1;
} else if (nRead == 0) {
endOfStream = PR_TRUE;
*dst = '\0';
return dst - buf;
}
inputHead = inputBuf;
inputTail = inputBuf + nRead;
goto loop;
}
PRInt32 DrainInputBuffer(char *buf, PRUint32 bufSize)
{
PRInt32 nBytes = inputTail - inputHead;
if (nBytes == 0) {
if (endOfStream) {
return -1;
} else {
return 0;
}
}
if ((PRInt32) bufSize < nBytes) {
nBytes = bufSize;
}
memcpy(buf, inputHead, nBytes);
inputHead += nBytes;
return nBytes;
}
PRStatus FetchFile(PRFileDesc *in, PRFileDesc *out)
{
char buf[FCOPY_BUFFER_SIZE];
PRInt32 nBytes;
while ((nBytes = DrainInputBuffer(buf, sizeof(buf))) > 0) {
if (PR_Write(out, buf, nBytes) != nBytes) {
fprintf(stderr, "httpget: cannot write to file\n");
return PR_FAILURE;
}
}
if (nBytes < 0) {
/* Input buffer is empty and end of stream */
return PR_SUCCESS;
}
while ((nBytes = PR_Read(in, buf, sizeof(buf))) > 0) {
if (PR_Write(out, buf, nBytes) != nBytes) {
fprintf(stderr, "httpget: cannot write to file\n");
return PR_FAILURE;
}
}
if (nBytes < 0) {
fprintf(stderr, "httpget: cannot read from socket\n");
return PR_FAILURE;
}
return PR_SUCCESS;
}
PRStatus FastFetchFile(PRFileDesc *in, PRFileDesc *out, PRUint32 size)
{
PRInt32 nBytes;
PRFileMap *outfMap;
void *addr;
char *start;
PRUint32 rem;
PRUint32 bytesToRead;
PRStatus rv;
PRInt64 sz64;
LL_UI2L(sz64, size);
outfMap = PR_CreateFileMap(out, sz64, PR_PROT_READWRITE);
PR_ASSERT(outfMap);
addr = PR_MemMap(outfMap, LL_ZERO, size);
if (addr == NULL) {
fprintf(stderr, "cannot memory-map file: (%d, %d)\n", PR_GetError(),
PR_GetOSError());
PR_CloseFileMap(outfMap);
return PR_FAILURE;
}
start = (char *) addr;
rem = size;
while ((nBytes = DrainInputBuffer(start, rem)) > 0) {
start += nBytes;
rem -= nBytes;
}
if (nBytes < 0) {
/* Input buffer is empty and end of stream */
return PR_SUCCESS;
}
bytesToRead = (rem < FCOPY_BUFFER_SIZE) ? rem : FCOPY_BUFFER_SIZE;
while (rem > 0 && (nBytes = PR_Read(in, start, bytesToRead)) > 0) {
start += nBytes;
rem -= nBytes;
bytesToRead = (rem < FCOPY_BUFFER_SIZE) ? rem : FCOPY_BUFFER_SIZE;
}
if (nBytes < 0) {
fprintf(stderr, "httpget: cannot read from socket\n");
return PR_FAILURE;
}
rv = PR_MemUnmap(addr, size);
PR_ASSERT(rv == PR_SUCCESS);
rv = PR_CloseFileMap(outfMap);
PR_ASSERT(rv == PR_SUCCESS);
return PR_SUCCESS;
}
PRStatus ParseURL(char *url, char *host, PRUint32 hostSize,
char *port, PRUint32 portSize, char *path, PRUint32 pathSize)
{
char *start, *end;
char *dst;
char *hostEnd;
char *portEnd;
char *pathEnd;
if (strncmp(url, "http", 4)) {
fprintf(stderr, "httpget: the protocol must be http\n");
return PR_FAILURE;
}
if (strncmp(url + 4, "://", 3) || url[7] == '\0') {
fprintf(stderr, "httpget: malformed URL: %s\n", url);
return PR_FAILURE;
}
start = end = url + 7;
dst = host;
hostEnd = host + hostSize;
while (*end && *end != ':' && *end != '/') {
if (dst == hostEnd - 1) {
fprintf(stderr, "httpget: host name too long\n");
return PR_FAILURE;
}
*(dst++) = *(end++);
}
*dst = '\0';
if (*end == '\0') {
PR_snprintf(port, portSize, "%d", 80);
PR_snprintf(path, pathSize, "%s", "/");
return PR_SUCCESS;
}
if (*end == ':') {
end++;
dst = port;
portEnd = port + portSize;
while (*end && *end != '/') {
if (dst == portEnd - 1) {
fprintf(stderr, "httpget: port number too long\n");
return PR_FAILURE;
}
*(dst++) = *(end++);
}
*dst = '\0';
if (*end == '\0') {
PR_snprintf(path, pathSize, "%s", "/");
return PR_SUCCESS;
}
} else {
PR_snprintf(port, portSize, "%d", 80);
}
dst = path;
pathEnd = path + pathSize;
while (*end) {
if (dst == pathEnd - 1) {
fprintf(stderr, "httpget: file pathname too long\n");
return PR_FAILURE;
}
*(dst++) = *(end++);
}
*dst = '\0';
return PR_SUCCESS;
}
void PrintUsage(void) {
fprintf(stderr, "usage: httpget url\n"
" httpget -o outputfile url\n"
" httpget url -o outputfile\n");
}
int main(int argc, char **argv)
{
PRHostEnt hostentry;
char buf[PR_NETDB_BUF_SIZE];
PRNetAddr addr;
PRFileDesc *socket = NULL, *file = NULL;
PRIntn cmdSize;
char host[HOST_SIZE];
char port[PORT_SIZE];
char path[PATH_SIZE];
char line[LINE_SIZE];
int exitStatus = 0;
PRBool endOfHeader = PR_FALSE;
char *url;
char *fileName = NULL;
PRUint32 fileSize;
if (argc != 2 && argc != 4) {
PrintUsage();
exit(1);
}
if (argc == 2) {
/*
* case 1: httpget url
*/
url = argv[1];
} else {
if (strcmp(argv[1], "-o") == 0) {
/*
* case 2: httpget -o outputfile url
*/
fileName = argv[2];
url = argv[3];
} else {
/*
* case 3: httpget url -o outputfile
*/
url = argv[1];
if (strcmp(argv[2], "-o") != 0) {
PrintUsage();
exit(1);
}
fileName = argv[3];
}
}
if (ParseURL(url, host, sizeof(host), port, sizeof(port),
path, sizeof(path)) == PR_FAILURE) {
exit(1);
}
if (PR_GetHostByName(host, buf, sizeof(buf), &hostentry)
== PR_FAILURE) {
fprintf(stderr, "httpget: unknown host name: %s\n", host);
exit(1);
}
addr.inet.family = PR_AF_INET;
addr.inet.port = PR_htons((short) atoi(port));
addr.inet.ip = *((PRUint32 *) hostentry.h_addr_list[0]);
socket = PR_NewTCPSocket();
if (socket == NULL) {
fprintf(stderr, "httpget: cannot create new tcp socket\n");
exit(1);
}
if (PR_Connect(socket, &addr, PR_INTERVAL_NO_TIMEOUT) == PR_FAILURE) {
fprintf(stderr, "httpget: cannot connect to http server\n");
exitStatus = 1;
goto done;
}
if (fileName == NULL) {
file = PR_STDOUT;
} else {
file = PR_Open(fileName, PR_RDWR | PR_CREATE_FILE | PR_TRUNCATE,
00777);
if (file == NULL) {
fprintf(stderr, "httpget: cannot open file %s: (%d, %d)\n",
fileName, PR_GetError(), PR_GetOSError());
exitStatus = 1;
goto done;
}
}
cmdSize = PR_snprintf(buf, sizeof(buf), "GET %s HTTP/1.0\r\n\r\n", path);
PR_ASSERT(cmdSize == (PRIntn) strlen("GET HTTP/1.0\r\n\r\n")
+ (PRIntn) strlen(path));
if (PR_Write(socket, buf, cmdSize) != cmdSize) {
fprintf(stderr, "httpget: cannot write to http server\n");
exitStatus = 1;
goto done;
}
if (ReadLine(socket, line, sizeof(line)) <= 0) {
fprintf(stderr, "httpget: cannot read line from http server\n");
exitStatus = 1;
goto done;
}
/* HTTP response: 200 == OK */
if (strstr(line, "200") == NULL) {
fprintf(stderr, "httpget: %s\n", line);
exitStatus = 1;
goto done;
}
while (ReadLine(socket, line, sizeof(line)) > 0) {
if (line[0] == '\n') {
endOfHeader = PR_TRUE;
break;
}
if (strncmp(line, "Content-Length", 14) == 0
|| strncmp(line, "Content-length", 14) == 0) {
char *p = line + 14;
while (*p == ' ' || *p == '\t') {
p++;
}
if (*p != ':') {
continue;
}
p++;
while (*p == ' ' || *p == '\t') {
p++;
}
fileSize = 0;
while ('0' <= *p && *p <= '9') {
fileSize = 10 * fileSize + (*p - '0');
p++;
}
}
}
if (endOfHeader == PR_FALSE) {
fprintf(stderr, "httpget: cannot read line from http server\n");
exitStatus = 1;
goto done;
}
if (fileName == NULL || fileSize == 0) {
FetchFile(socket, file);
} else {
FastFetchFile(socket, file, fileSize);
}
done:
if (socket) PR_Close(socket);
if (file) PR_Close(file);
PR_Cleanup();
return exitStatus;
}