networking/wget.c

/* vi: set sw=4 ts=4: */
/*
 * wget - retrieve a file using HTTP or FTP
 *
 * Chip Rosenthal Covad Communications <chip@laserlink.net>
 *
 */

#include <getopt.h>	/* for struct option */
#include "libbb.h"

struct host_info {
	// May be used if we ever will want to free() all xstrdup()s...
	/* char *allocated; */
	const char *path;
	const char *user;
	char       *host;
	int         port;
	smallint    is_ftp;
};


/* Globals (can be accessed from signal handlers) */
struct globals {
	off_t content_len;        /* Content-length of the file */
	off_t beg_range;          /* Range at which continue begins */
#if ENABLE_FEATURE_WGET_STATUSBAR
	off_t lastsize;
	off_t totalsize;
	off_t transferred;        /* Number of bytes transferred so far */
	const char *curfile;      /* Name of current file being transferred */
	unsigned lastupdate_sec;
	unsigned start_sec;
#endif
	smallint chunked;             /* chunked transfer encoding */
};
#define G (*(struct globals*)&bb_common_bufsiz1)
struct BUG_G_too_big {
	char BUG_G_too_big[sizeof(G) <= COMMON_BUFSIZE ? 1 : -1];
};
#define content_len     (G.content_len    )
#define beg_range       (G.beg_range      )
#define lastsize        (G.lastsize       )
#define totalsize       (G.totalsize      )
#define transferred     (G.transferred    )
#define curfile         (G.curfile        )
#define lastupdate_sec  (G.lastupdate_sec )
#define start_sec       (G.start_sec      )
#define chunked         (G.chunked        )
#define INIT_G() do { } while (0)


#if ENABLE_FEATURE_WGET_STATUSBAR
enum {
	STALLTIME = 5                   /* Seconds when xfer considered "stalled" */
};

static int getttywidth(void)
{
	int width;
	get_terminal_width_height(0, &width, NULL);
	return width;
}

static void progressmeter(int flag)
{
	/* We can be called from signal handler */
	int save_errno = errno;
	off_t abbrevsize;
	unsigned since_last_update, elapsed;
	unsigned ratio;
	int barlength, i;

	if (flag == -1) { /* first call to progressmeter */
		start_sec = monotonic_sec();
		lastupdate_sec = start_sec;
		lastsize = 0;
		totalsize = content_len + beg_range; /* as content_len changes.. */
	}

	ratio = 100;
	if (totalsize != 0 && !chunked) {
		/* long long helps to have it working even if !LFS */
		ratio = (unsigned) (100ULL * (transferred+beg_range) / totalsize);
		if (ratio > 100) ratio = 100;
	}

	fprintf(stderr, "\r%-20.20s%4d%% ", curfile, ratio);

	barlength = getttywidth() - 49;
	if (barlength > 0) {
		/* god bless gcc for variable arrays :) */
		i = barlength * ratio / 100;
		{
			char buf[i+1];
			memset(buf, '*', i);
			buf[i] = '\0';
			fprintf(stderr, "|%s%*s|", buf, barlength - i, "");
		}
	}
	i = 0;
	abbrevsize = transferred + beg_range;
	while (abbrevsize >= 100000) {
		i++;
		abbrevsize >>= 10;
	}
	/* see http://en.wikipedia.org/wiki/Tera */
	fprintf(stderr, "%6d%c ", (int)abbrevsize, " kMGTPEZY"[i]);

// Nuts! Ain't it easier to update progress meter ONLY when we transferred++?

	elapsed = monotonic_sec();
	since_last_update = elapsed - lastupdate_sec;
	if (transferred > lastsize) {
		lastupdate_sec = elapsed;
		lastsize = transferred;
		if (since_last_update >= STALLTIME) {
			/* We "cut off" these seconds from elapsed time
			 * by adjusting start time */
			start_sec += since_last_update;
		}
		since_last_update = 0; /* we are un-stalled now */
	}
	elapsed -= start_sec; /* now it's "elapsed since start" */

	if (since_last_update >= STALLTIME) {
		fprintf(stderr, " - stalled -");
	} else {
		off_t to_download = totalsize - beg_range;
		if (transferred <= 0 || (int)elapsed <= 0 || transferred > to_download || chunked) {
			fprintf(stderr, "--:--:-- ETA");
		} else {
			/* to_download / (transferred/elapsed) - elapsed: */
			int eta = (int) ((unsigned long long)to_download*elapsed/transferred - elapsed);
			/* (long long helps to have working ETA even if !LFS) */
			i = eta % 3600;
			fprintf(stderr, "%02d:%02d:%02d ETA", eta / 3600, i / 60, i % 60);
		}
	}

	if (flag == 0) {
		/* last call to progressmeter */
		alarm(0);
		transferred = 0;
		fputc('\n', stderr);
	} else {
		if (flag == -1) { /* first call to progressmeter */
			signal_SA_RESTART_empty_mask(SIGALRM, progressmeter);
		}
		alarm(1);
	}

	errno = save_errno;
}
/* Original copyright notice which applies to the CONFIG_FEATURE_WGET_STATUSBAR stuff,
 * much of which was blatantly stolen from openssh.  */
/*-
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. <BSD Advertising Clause omitted per the July 22, 1999 licensing change
 *		ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change>
 *
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */
#else /* FEATURE_WGET_STATUSBAR */

static ALWAYS_INLINE void progressmeter(int flag) { }

#endif


/* Read NMEMB bytes into PTR from STREAM.  Returns the number of bytes read,
 * and a short count if an eof or non-interrupt error is encountered.  */
static size_t safe_fread(void *ptr, size_t nmemb, FILE *stream)
{
	size_t ret;
	char *p = (char*)ptr;

	do {
		clearerr(stream);
		ret = fread(p, 1, nmemb, stream);
		p += ret;
		nmemb -= ret;
	} while (nmemb && ferror(stream) && errno == EINTR);

	return p - (char*)ptr;
}

/* Read a line or SIZE-1 bytes into S, whichever is less, from STREAM.
 * Returns S, or NULL if an eof or non-interrupt error is encountered.  */
static char *safe_fgets(char *s, int size, FILE *stream)
{
	char *ret;

	do {
		clearerr(stream);
		ret = fgets(s, size, stream);
	} while (ret == NULL && ferror(stream) && errno == EINTR);

	return ret;
}

#if ENABLE_FEATURE_WGET_AUTHENTICATION
/* Base64-encode character string. buf is assumed to be char buf[512]. */
static char *base64enc_512(char buf[512], const char *str)
{
	unsigned len = strlen(str);
	if (len > 512/4*3 - 10) /* paranoia */
		len = 512/4*3 - 10;
	bb_uuencode(buf, str, len, bb_uuenc_tbl_base64);
	return buf;
}
#endif


static FILE *open_socket(len_and_sockaddr *lsa)
{
	FILE *fp;

	/* glibc 2.4 seems to try seeking on it - ??! */
	/* hopefully it understands what ESPIPE means... */
	fp = fdopen(xconnect_stream(lsa), "r+");
	if (fp == NULL)
		bb_perror_msg_and_die("fdopen");

	return fp;
}


static int ftpcmd(const char *s1, const char *s2, FILE *fp, char *buf)
{
	int result;
	if (s1) {
		if (!s2) s2 = "";
		fprintf(fp, "%s%s\r\n", s1, s2);
		fflush(fp);
	}

	do {
		char *buf_ptr;

		if (fgets(buf, 510, fp) == NULL) {
			bb_perror_msg_and_die("error getting response");
		}
		buf_ptr = strstr(buf, "\r\n");
		if (buf_ptr) {
			*buf_ptr = '\0';
		}
	} while (!isdigit(buf[0]) || buf[3] != ' ');

	buf[3] = '\0';
	result = xatoi_u(buf);
	buf[3] = ' ';
	return result;
}


static void parse_url(char *src_url, struct host_info *h)
{
	char *url, *p, *sp;

	/* h->allocated = */ url = xstrdup(src_url);

	if (strncmp(url, "http://", 7) == 0) {
		h->port = bb_lookup_port("http", "tcp", 80);
		h->host = url + 7;
		h->is_ftp = 0;
	} else if (strncmp(url, "ftp://", 6) == 0) {
		h->port = bb_lookup_port("ftp", "tcp", 21);
		h->host = url + 6;
		h->is_ftp = 1;
	} else
		bb_error_msg_and_die("not an http or ftp url: %s", url);

	// FYI:
	// "Real" wget 'http://busybox.net?var=a/b' sends this request:
	//   'GET /?var=a/b HTTP 1.0'
	//   and saves 'index.html?var=a%2Fb' (we save 'b')
	// wget 'http://busybox.net?login=john@doe':
	//   request: 'GET /?login=john@doe HTTP/1.0'
	//   saves: 'index.html?login=john@doe' (we save '?login=john@doe')
	// wget 'http://busybox.net#test/test':
	//   request: 'GET / HTTP/1.0'
	//   saves: 'index.html' (we save 'test')
	//
	// We also don't add unique .N suffix if file exists...
	sp = strchr(h->host, '/');
	p = strchr(h->host, '?'); if (!sp || (p && sp > p)) sp = p;
	p = strchr(h->host, '#'); if (!sp || (p && sp > p)) sp = p;
	if (!sp) {
		h->path = "";
	} else if (*sp == '/') {
		*sp = '\0';
		h->path = sp + 1;
	} else { // '#' or '?'
		// http://busybox.net?login=john@doe is a valid URL
		// memmove converts to:
		// http:/busybox.nett?login=john@doe...
		memmove(h->host - 1, h->host, sp - h->host);
		h->host--;
		sp[-1] = '\0';
		h->path = sp;
	}

	sp = strrchr(h->host, '@');
	h->user = NULL;
	if (sp != NULL) {
		h->user = h->host;
		*sp = '\0';
		h->host = sp + 1;
	}

	sp = h->host;
}


static char *gethdr(char *buf, size_t bufsiz, FILE *fp /*, int *istrunc*/)
{
	char *s, *hdrval;
	int c;

	/* *istrunc = 0; */

	/* retrieve header line */
	if (fgets(buf, bufsiz, fp) == NULL)
		return NULL;

	/* see if we are at the end of the headers */
	for (s = buf; *s == '\r'; ++s)
		continue;
	if (*s == '\n')
		return NULL;

	/* convert the header name to lower case */
	for (s = buf; isalnum(*s) || *s == '-' || *s == '.'; ++s)
		*s = tolower(*s);

	/* verify we are at the end of the header name */
	if (*s != ':')
		bb_error_msg_and_die("bad header line: %s", buf);

	/* locate the start of the header value */
	*s++ = '\0';
	hdrval = skip_whitespace(s);

	/* locate the end of header */
	while (*s && *s != '\r' && *s != '\n')
		++s;

	/* end of header found */
	if (*s) {
		*s = '\0';
		return hdrval;
	}

	/* Rats! The buffer isn't big enough to hold the entire header value. */
	while (c = getc(fp), c != EOF && c != '\n')
		continue;
	/* *istrunc = 1; */
	return hdrval;
}


int wget_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int wget_main(int argc, char **argv)
{
	char buf[512];
	struct host_info server, target;
	len_and_sockaddr *lsa;
	int status;
	int port;
	int try = 5;
	unsigned opt;
	char *str;
	char *proxy = 0;
	char *dir_prefix = NULL;
#if ENABLE_FEATURE_WGET_LONG_OPTIONS
	char *extra_headers = NULL;
	llist_t *headers_llist = NULL;
#endif
	FILE *sfp = NULL;               /* socket to web/ftp server         */
	FILE *dfp;                      /* socket to ftp server (data)      */
	char *fname_out;                /* where to direct output (-O)      */
	bool got_clen = 0;              /* got content-length: from server  */
	int output_fd = -1;
	bool use_proxy = 1;             /* Use proxies if env vars are set  */
	const char *proxy_flag = "on";  /* Use proxies if env vars are set  */
	const char *user_agent = "Wget";/* "User-Agent" header field        */

	static const char keywords[] ALIGN1 =
		"content-length\0""transfer-encoding\0""chunked\0""location\0";
	enum {
		KEY_content_length = 1, KEY_transfer_encoding, KEY_chunked, KEY_location
	};
	enum {
		WGET_OPT_CONTINUE   = 0x1,
		WGET_OPT_SPIDER	    = 0x2,
		WGET_OPT_QUIET      = 0x4,
		WGET_OPT_OUTNAME    = 0x8,
		WGET_OPT_PREFIX     = 0x10,
		WGET_OPT_PROXY      = 0x20,
		WGET_OPT_USER_AGENT = 0x40,
		WGET_OPT_PASSIVE    = 0x80,
		WGET_OPT_HEADER     = 0x100,
	};
#if ENABLE_FEATURE_WGET_LONG_OPTIONS
	static const char wget_longopts[] ALIGN1 =
		/* name, has_arg, val */
		"continue\0"         No_argument       "c"
		"spider\0"           No_argument       "s"
		"quiet\0"            No_argument       "q"
		"output-document\0"  Required_argument "O"
		"directory-prefix\0" Required_argument "P"
		"proxy\0"            Required_argument "Y"
		"user-agent\0"       Required_argument "U"
		"passive-ftp\0"      No_argument       "\xff"
		"header\0"           Required_argument "\xfe"
		;
#endif

	INIT_G();

#if ENABLE_FEATURE_WGET_LONG_OPTIONS
	applet_long_options = wget_longopts;
#endif
	/* server.allocated = target.allocated = NULL; */
	opt_complementary = "-1" USE_FEATURE_WGET_LONG_OPTIONS(":\xfe::");
	opt = getopt32(argv, "csqO:P:Y:U:",
				&fname_out, &dir_prefix,
				&proxy_flag, &user_agent
				USE_FEATURE_WGET_LONG_OPTIONS(, &headers_llist)
				);
	if (strcmp(proxy_flag, "off") == 0) {
		/* Use the proxy if necessary */
		use_proxy = 0;
	}
#if ENABLE_FEATURE_WGET_LONG_OPTIONS
	if (headers_llist) {
		int size = 1;
		char *cp;
		llist_t *ll = headers_llist;
		while (ll) {
			size += strlen(ll->data) + 2;
			ll = ll->link;
		}
		extra_headers = cp = xmalloc(size);
		while (headers_llist) {
			cp += sprintf(cp, "%s\r\n", headers_llist->data);
			headers_llist = headers_llist->link;
		}
	}
#endif

	parse_url(argv[optind], &target);
	server.host = target.host;
	server.port = target.port;

	/* Use the proxy if necessary */
	if (use_proxy) {
		proxy = getenv(target.is_ftp ? "ftp_proxy" : "http_proxy");
		if (proxy && *proxy) {
			parse_url(proxy, &server);
		} else {
			use_proxy = 0;
		}
	}

	/* Guess an output filename, if there was no -O FILE */
	if (!(opt & WGET_OPT_OUTNAME)) {
		fname_out = bb_get_last_path_component_nostrip(target.path);
		/* handle "wget http://kernel.org//" */
		if (fname_out[0] == '/' || !fname_out[0])
			fname_out = (char*)"index.html";
		/* -P DIR is considered only if there was no -O FILE */
		if (dir_prefix)
			fname_out = concat_path_file(dir_prefix, fname_out);
	} else {
		if (LONE_DASH(fname_out)) {
			/* -O - */
			output_fd = 1;
			opt &= ~WGET_OPT_CONTINUE;
		}
	}
#if ENABLE_FEATURE_WGET_STATUSBAR
	curfile = bb_get_last_path_component_nostrip(fname_out);
#endif

	/* Impossible?
	if ((opt & WGET_OPT_CONTINUE) && !fname_out)
		bb_error_msg_and_die("cannot specify continue (-c) without a filename (-O)"); */

	/* Determine where to start transfer */
	if (opt & WGET_OPT_CONTINUE) {
		output_fd = open(fname_out, O_WRONLY);
		if (output_fd >= 0) {
			beg_range = xlseek(output_fd, 0, SEEK_END);
		}
		/* File doesn't exist. We do not create file here yet.
		   We are not sure it exists on remove side */
	}

	/* We want to do exactly _one_ DNS lookup, since some
	 * sites (i.e. ftp.us.debian.org) use round-robin DNS
	 * and we want to connect to only one IP... */
	lsa = xhost2sockaddr(server.host, server.port);
	if (!(opt & WGET_OPT_QUIET)) {
		fprintf(stderr, "Connecting to %s (%s)\n", server.host,
				xmalloc_sockaddr2dotted(&lsa->u.sa));
		/* We leak result of xmalloc_sockaddr2dotted */
	}

	if (use_proxy || !target.is_ftp) {
		/*
		 *  HTTP session
		 */
		do {
			got_clen = 0;
			chunked = 0;

			if (!--try)
				bb_error_msg_and_die("too many redirections");

			/* Open socket to http server */
			if (sfp) fclose(sfp);
			sfp = open_socket(lsa);

			/* Send HTTP request.  */
			if (use_proxy) {
				fprintf(sfp, "GET %stp://%s/%s HTTP/1.1\r\n",
					target.is_ftp ? "f" : "ht", target.host,
					target.path);
			} else {
				fprintf(sfp, "GET /%s HTTP/1.1\r\n", target.path);
			}

			fprintf(sfp, "Host: %s\r\nUser-Agent: %s\r\n",
				target.host, user_agent);

#if ENABLE_FEATURE_WGET_AUTHENTICATION
			if (target.user) {
				fprintf(sfp, "Proxy-Authorization: Basic %s\r\n"+6,
					base64enc_512(buf, target.user));
			}
			if (use_proxy && server.user) {
				fprintf(sfp, "Proxy-Authorization: Basic %s\r\n",
					base64enc_512(buf, server.user));
			}
#endif

			if (beg_range)
				fprintf(sfp, "Range: bytes=%"OFF_FMT"d-\r\n", beg_range);
#if ENABLE_FEATURE_WGET_LONG_OPTIONS
			if (extra_headers)
				fputs(extra_headers, sfp);
#endif
			fprintf(sfp, "Connection: close\r\n\r\n");

			/*
			* Retrieve HTTP response line and check for "200" status code.
			*/
 read_response:
			if (fgets(buf, sizeof(buf), sfp) == NULL)
				bb_error_msg_and_die("no response from server");

			str = buf;
			str = skip_non_whitespace(str);
			str = skip_whitespace(str);
			// FIXME: no error check
			// xatou wouldn't work: "200 OK"
			status = atoi(str);
			switch (status) {
			case 0:
			case 100:
				while (gethdr(buf, sizeof(buf), sfp /*, &n*/) != NULL)
					/* eat all remaining headers */;
				goto read_response;
			case 200:
				break;
			case 300:	/* redirection */
			case 301:
			case 302:
			case 303:
				break;
			case 206:
				if (beg_range)
					break;
				/* fall through */
			default:
				/* Show first line only and kill any ESC tricks */
				buf[strcspn(buf, "\n\r\x1b")] = '\0';
				bb_error_msg_and_die("server returned error: %s", buf);
			}

			/*
			 * Retrieve HTTP headers.
			 */
			while ((str = gethdr(buf, sizeof(buf), sfp /*, &n*/)) != NULL) {
				/* gethdr did already convert the "FOO:" string to lowercase */
				smalluint key = index_in_strings(keywords, *&buf) + 1;
				if (key == KEY_content_length) {
					content_len = BB_STRTOOFF(str, NULL, 10);
					if (errno || content_len < 0) {
						bb_error_msg_and_die("content-length %s is garbage", str);
					}
					got_clen = 1;
					continue;
				}
				if (key == KEY_transfer_encoding) {
					if (index_in_strings(keywords, str_tolower(str)) + 1 != KEY_chunked)
						bb_error_msg_and_die("transfer encoding '%s' is not supported", str);
					chunked = got_clen = 1;
				}
				if (key == KEY_location) {
					if (str[0] == '/')
						/* free(target.allocated); */
						target.path = /* target.allocated = */ xstrdup(str+1);
					else {
						parse_url(str, &target);
						if (use_proxy == 0) {
							server.host = target.host;
							server.port = target.port;
						}
						free(lsa);
						lsa = xhost2sockaddr(server.host, server.port);
						break;
					}
				}
			}
		} while (status >= 300);

		dfp = sfp;

	} else {

		/*
		 *  FTP session
		 */
		if (!target.user)
			target.user = xstrdup("anonymous:busybox@");

		sfp = open_socket(lsa);
		if (ftpcmd(NULL, NULL, sfp, buf) != 220)
			bb_error_msg_and_die("%s", buf+4);

		/*
		 * Splitting username:password pair,
		 * trying to log in
		 */
		str = strchr(target.user, ':');
		if (str)
			*(str++) = '\0';
		switch (ftpcmd("USER ", target.user, sfp, buf)) {
		case 230:
			break;
		case 331:
			if (ftpcmd("PASS ", str, sfp, buf) == 230)
				break;
			/* fall through (failed login) */
		default:
			bb_error_msg_and_die("ftp login: %s", buf+4);
		}

		ftpcmd("TYPE I", NULL, sfp, buf);

		/*
		 * Querying file size
		 */
		if (ftpcmd("SIZE ", target.path, sfp, buf) == 213) {
			content_len = BB_STRTOOFF(buf+4, NULL, 10);
			if (errno || content_len < 0) {
				bb_error_msg_and_die("SIZE value is garbage");
			}
			got_clen = 1;
		}

		/*
		 * Entering passive mode
		 */
		if (ftpcmd("PASV", NULL, sfp, buf) != 227) {
 pasv_error:
			bb_error_msg_and_die("bad response to %s: %s", "PASV", buf);
		}
		// Response is "227 garbageN1,N2,N3,N4,P1,P2[)garbage]
		// Server's IP is N1.N2.N3.N4 (we ignore it)
		// Server's port for data connection is P1*256+P2
		str = strrchr(buf, ')');
		if (str) str[0] = '\0';
		str = strrchr(buf, ',');
		if (!str) goto pasv_error;
		port = xatou_range(str+1, 0, 255);
		*str = '\0';
		str = strrchr(buf, ',');
		if (!str) goto pasv_error;
		port += xatou_range(str+1, 0, 255) * 256;
		set_nport(lsa, htons(port));
		dfp = open_socket(lsa);

		if (beg_range) {
			sprintf(buf, "REST %"OFF_FMT"d", beg_range);
			if (ftpcmd(buf, NULL, sfp, buf) == 350)
				content_len -= beg_range;
		}

		if (ftpcmd("RETR ", target.path, sfp, buf) > 150)
			bb_error_msg_and_die("bad response to %s: %s", "RETR", buf);
	}

	if (opt & WGET_OPT_SPIDER) {
		if (ENABLE_FEATURE_CLEAN_UP)
			fclose(sfp);
		return EXIT_SUCCESS;
	}

	/*
	 * Retrieve file
	 */

	/* Do it before progressmeter (want to have nice error message) */
	if (output_fd < 0) {
		int o_flags = O_WRONLY | O_CREAT | O_TRUNC | O_EXCL;
		/* compat with wget: -O FILE can overwrite */
		if (opt & WGET_OPT_OUTNAME)
			o_flags = O_WRONLY | O_CREAT | O_TRUNC;
		output_fd = xopen(fname_out, o_flags);
	}

	if (!(opt & WGET_OPT_QUIET))
		progressmeter(-1);

	if (chunked)
		goto get_clen;

	/* Loops only if chunked */
	while (1) {
		while (content_len > 0 || !got_clen) {
			int n;
			unsigned rdsz = sizeof(buf);

			if (content_len < sizeof(buf) && (chunked || got_clen))
				rdsz = (unsigned)content_len;
			n = safe_fread(buf, rdsz, dfp);
			if (n <= 0) {
				if (ferror(dfp)) {
					/* perror will not work: ferror doesn't set errno */
					bb_error_msg_and_die(bb_msg_read_error);
				}
				break;
			}
			xwrite(output_fd, buf, n);
#if ENABLE_FEATURE_WGET_STATUSBAR
			transferred += n;
#endif
			if (got_clen)
				content_len -= n;
		}

		if (!chunked)
			break;

		safe_fgets(buf, sizeof(buf), dfp); /* This is a newline */
 get_clen:
		safe_fgets(buf, sizeof(buf), dfp);
		content_len = STRTOOFF(buf, NULL, 16);
		/* FIXME: error check? */
		if (content_len == 0)
			break; /* all done! */
	}

	if (!(opt & WGET_OPT_QUIET))
		progressmeter(0);

	if ((use_proxy == 0) && target.is_ftp) {
		fclose(dfp);
		if (ftpcmd(NULL, NULL, sfp, buf) != 226)
			bb_error_msg_and_die("ftp error: %s", buf+4);
		ftpcmd("QUIT", NULL, sfp, buf);
	}

	return EXIT_SUCCESS;
}