diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 17:04:52 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 17:04:52 +0000 |
commit | 5e03c718f4e7ff13cb6834eda737c269ebed02ad (patch) | |
tree | bfad3f5be123f000fdb03e26400050dece33d72f /src/retr.c | |
parent | Initial commit. (diff) | |
download | wget-upstream.tar.xz wget-upstream.zip |
Adding upstream version 1.21.3.upstream/1.21.3upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | src/retr.c | 1575 |
1 files changed, 1575 insertions, 0 deletions
diff --git a/src/retr.c b/src/retr.c new file mode 100644 index 0000000..615802f --- /dev/null +++ b/src/retr.c @@ -0,0 +1,1575 @@ +/* File retrieval. + Copyright (C) 1996-2011, 2014-2015, 2018-2022 Free Software + Foundation, Inc. + +This file is part of GNU Wget. + +GNU Wget is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 3 of the License, or (at +your option) any later version. + +GNU Wget is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with Wget. If not, see <http://www.gnu.org/licenses/>. + +Additional permission under GNU GPL version 3 section 7 + +If you modify this program, or any covered work, by linking or +combining it with the OpenSSL project's OpenSSL library (or a +modified version of that library), containing parts covered by the +terms of the OpenSSL or SSLeay licenses, the Free Software Foundation +grants you additional permission to convey the resulting work. +Corresponding Source for a non-source form of such a combination +shall include the source code for the parts of OpenSSL used as well +as that of the covered work. */ + +#include "wget.h" + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <errno.h> +#include <string.h> +#include <assert.h> +#ifdef VMS +# include <unixio.h> /* For delete(). */ +#endif + +#ifdef HAVE_LIBZ +# include <zlib.h> +#endif + +#include "exits.h" +#include "utils.h" +#include "retr.h" +#include "progress.h" +#include "url.h" +#include "recur.h" +#include "ftp.h" +#include "http.h" +#include "host.h" +#include "connect.h" +#include "hash.h" +#include "convert.h" +#include "ptimer.h" +#include "html-url.h" +#include "iri.h" +#include "hsts.h" + +/* Total size of downloaded files. Used to enforce quota. */ +wgint total_downloaded_bytes; + +/* Total download time in seconds. */ +double total_download_time; + +/* If non-NULL, the stream to which output should be written. This + stream is initialized when `-O' is used. */ +FILE *output_stream; + +/* Whether output_document is a regular file we can manipulate, + i.e. not `-' or a device file. */ +bool output_stream_regular; + +static struct { + wgint chunk_bytes; + double chunk_start; + double sleep_adjust; +} limit_data; + +static void +limit_bandwidth_reset (void) +{ + xzero (limit_data); +} + +#ifdef HAVE_LIBZ +static voidpf +zalloc (voidpf opaque, unsigned int items, unsigned int size) +{ + (void) opaque; + return (voidpf) xcalloc (items, size); +} + +static void +zfree (voidpf opaque, voidpf address) +{ + (void) opaque; + xfree (address); +} +#endif + +/* Limit the bandwidth by pausing the download for an amount of time. + BYTES is the number of bytes received from the network, and TIMER + is the timer that started at the beginning of download. */ + +static void +limit_bandwidth (wgint bytes, struct ptimer *timer) +{ + double delta_t = ptimer_read (timer) - limit_data.chunk_start; + double expected; + + limit_data.chunk_bytes += bytes; + + /* Calculate the amount of time we expect downloading the chunk + should take. If in reality it took less time, sleep to + compensate for the difference. */ + expected = (double) limit_data.chunk_bytes / opt.limit_rate; + + if (expected > delta_t) + { + double slp = expected - delta_t + limit_data.sleep_adjust; + double t0, t1; + if (slp < 0.2) + { + DEBUGP (("deferring a %.2f ms sleep (%s/%.2f).\n", + slp * 1000, number_to_static_string (limit_data.chunk_bytes), + delta_t)); + return; + } + DEBUGP (("\nsleeping %.2f ms for %s bytes, adjust %.2f ms\n", + slp * 1000, number_to_static_string (limit_data.chunk_bytes), + limit_data.sleep_adjust)); + + t0 = ptimer_read (timer); + xsleep (slp); + t1 = ptimer_measure (timer); + + /* Due to scheduling, we probably slept slightly longer (or + shorter) than desired. Calculate the difference between the + desired and the actual sleep, and adjust the next sleep by + that amount. */ + limit_data.sleep_adjust = slp - (t1 - t0); + /* If sleep_adjust is very large, it's likely due to suspension + and not clock inaccuracy. Don't enforce those. */ + if (limit_data.sleep_adjust > 0.5) + limit_data.sleep_adjust = 0.5; + else if (limit_data.sleep_adjust < -0.5) + limit_data.sleep_adjust = -0.5; + } + + limit_data.chunk_bytes = 0; + limit_data.chunk_start = ptimer_read (timer); +} + +/* Write data in BUF to OUT. However, if *SKIP is non-zero, skip that + amount of data and decrease SKIP. Increment *TOTAL by the amount + of data written. If OUT2 is not NULL, also write BUF to OUT2. + In case of error writing to OUT, -2 is returned. In case of error + writing to OUT2, -3 is returned. Return 1 if the whole BUF was + skipped. */ + +static int +write_data (FILE *out, FILE *out2, const char *buf, int bufsize, + wgint *skip, wgint *written) +{ + if (out == NULL && out2 == NULL) + return 1; + + if (skip) + { + if (*skip > bufsize) + { + *skip -= bufsize; + return 1; + } + if (*skip) + { + buf += *skip; + bufsize -= *skip; + *skip = 0; + if (bufsize == 0) + return 1; + } + } + + if (out) + fwrite (buf, 1, bufsize, out); + if (out2) + fwrite (buf, 1, bufsize, out2); + + if (written) + *written += bufsize; + + /* Immediately flush the downloaded data. This should not hinder + performance: fast downloads will arrive in large 16K chunks + (which stdio would write out immediately anyway), and slow + downloads wouldn't be limited by disk speed. */ + + /* 2005-04-20 SMS. + Perhaps it shouldn't hinder performance, but it sure does, at least + on VMS (more than 2X). Rather than speculate on what it should or + shouldn't do, it might make more sense to test it. Even better, it + might be nice to explain what possible benefit it could offer, as + it appears to be a clear invitation to poor performance with no + actual justification. (Also, why 16K? Anyone test other values?) + */ +#ifndef __VMS + if (out) + fflush (out); + if (out2) + fflush (out2); +#endif /* ndef __VMS */ + + if (out && ferror (out)) + return -2; + else if (out2 && ferror (out2)) + return -3; + + return 0; +} + +/* Read the contents of file descriptor FD until it the connection + terminates or a read error occurs. The data is read in portions of + up to 16K and written to OUT as it arrives. If opt.verbose is set, + the progress is shown. + + TOREAD is the amount of data expected to arrive, normally only used + by the progress gauge. + + STARTPOS is the position from which the download starts, used by + the progress gauge. If QTYREAD is non-NULL, the value it points to + is incremented by the amount of data read from the network. If + QTYWRITTEN is non-NULL, the value it points to is incremented by + the amount of data written to disk. The time it took to download + the data is stored to ELAPSED. + + If OUT2 is non-NULL, the contents is also written to OUT2. + OUT2 will get an exact copy of the response: if this is a chunked + response, everything -- including the chunk headers -- is written + to OUT2. (OUT will only get the unchunked response.) + + The function exits and returns the amount of data read. In case of + error while reading data, -1 is returned. In case of error while + writing data to OUT, -2 is returned. In case of error while writing + data to OUT2, -3 is returned. */ + +int +fd_read_body (const char *downloaded_filename, int fd, FILE *out, wgint toread, wgint startpos, + + wgint *qtyread, wgint *qtywritten, double *elapsed, int flags, + FILE *out2) +{ + int ret = 0; +#undef max +#define max(a,b) ((a) > (b) ? (a) : (b)) + int dlbufsize = max (BUFSIZ, 8 * 1024); + char *dlbuf = xmalloc (dlbufsize); + + struct ptimer *timer = NULL; + double last_successful_read_tm = 0; + + /* The progress gauge, set according to the user preferences. */ + void *progress = NULL; + + /* Non-zero if the progress gauge is interactive, i.e. if it can + continually update the display. When true, smaller timeout + values are used so that the gauge can update the display when + data arrives slowly. */ + bool progress_interactive = false; + + bool exact = !!(flags & rb_read_exactly); + + /* Used only by HTTP/HTTPS chunked transfer encoding. */ + bool chunked = flags & rb_chunked_transfer_encoding; + wgint skip = 0; + + /* How much data we've read/written. */ + wgint sum_read = 0; + wgint sum_written = 0; + wgint remaining_chunk_size = 0; + +#ifdef HAVE_LIBZ + /* try to minimize the number of calls to inflate() and write_data() per + call to fd_read() */ + unsigned int gzbufsize = dlbufsize * 4; + char *gzbuf = NULL; + z_stream gzstream; + + if (flags & rb_compressed_gzip) + { + gzbuf = xmalloc (gzbufsize); + if (gzbuf != NULL) + { + gzstream.zalloc = zalloc; + gzstream.zfree = zfree; + gzstream.opaque = Z_NULL; + gzstream.next_in = Z_NULL; + gzstream.avail_in = 0; + + #define GZIP_DETECT 32 /* gzip format detection */ + #define GZIP_WINDOW 15 /* logarithmic window size (default: 15) */ + ret = inflateInit2 (&gzstream, GZIP_DETECT | GZIP_WINDOW); + if (ret != Z_OK) + { + xfree (gzbuf); + errno = (ret == Z_MEM_ERROR) ? ENOMEM : EINVAL; + ret = -1; + goto out; + } + } + else + { + errno = ENOMEM; + ret = -1; + goto out; + } + } +#endif + + if (flags & rb_skip_startpos) + skip = startpos; + + if (opt.show_progress) + { + const char *filename_progress; + /* If we're skipping STARTPOS bytes, pass 0 as the INITIAL + argument to progress_create because the indicator doesn't + (yet) know about "skipping" data. */ + wgint start = skip ? 0 : startpos; + if (opt.dir_prefix) + filename_progress = downloaded_filename + strlen (opt.dir_prefix) + 1; + else + filename_progress = downloaded_filename; + progress = progress_create (filename_progress, start, start + toread); + progress_interactive = progress_interactive_p (progress); + } + + if (opt.limit_rate) + limit_bandwidth_reset (); + + /* A timer is needed for tracking progress, for throttling, and for + tracking elapsed time. If either of these are requested, start + the timer. */ + if (progress || opt.limit_rate || elapsed) + { + timer = ptimer_new (); + last_successful_read_tm = 0; + } + + /* Use a smaller buffer for low requested bandwidths. For example, + with --limit-rate=2k, it doesn't make sense to slurp in 16K of + data and then sleep for 8s. With buffer size equal to the limit, + we never have to sleep for more than one second. */ + if (opt.limit_rate && opt.limit_rate < dlbufsize) + dlbufsize = opt.limit_rate; + + /* Read from FD while there is data to read. Normally toread==0 + means that it is unknown how much data is to arrive. However, if + EXACT is set, then toread==0 means what it says: that no data + should be read. */ + while (!exact || (sum_read < toread)) + { + int rdsize; + double tmout = opt.read_timeout; + + if (chunked) + { + if (remaining_chunk_size == 0) + { + char *line = fd_read_line (fd); + char *endl; + if (line == NULL) + { + ret = -1; + break; + } + else if (out2 != NULL) + fwrite (line, 1, strlen (line), out2); + + remaining_chunk_size = strtol (line, &endl, 16); + xfree (line); + + if (remaining_chunk_size < 0) + { + ret = -1; + break; + } + + if (remaining_chunk_size == 0) + { + ret = 0; + line = fd_read_line (fd); + if (line == NULL) + ret = -1; + else + { + if (out2 != NULL) + fwrite (line, 1, strlen (line), out2); + xfree (line); + } + break; + } + } + + rdsize = MIN (remaining_chunk_size, dlbufsize); + } + else + rdsize = exact ? MIN (toread - sum_read, dlbufsize) : dlbufsize; + + if (progress_interactive) + { + /* For interactive progress gauges, always specify a ~1s + timeout, so that the gauge can be updated regularly even + when the data arrives very slowly or stalls. */ + tmout = 0.95; + /* avoid wrong 'interactive timeout' */ + errno = 0; + if (opt.read_timeout) + { + double waittm; + waittm = ptimer_read (timer) - last_successful_read_tm; + if (waittm + tmout > opt.read_timeout) + { + /* Don't let total idle time exceed read timeout. */ + tmout = opt.read_timeout - waittm; + /* if 0 fd_read can be 'blocked read' */ + if (tmout <= 0) + { + /* We've already exceeded the timeout. */ + ret = -1, errno = ETIMEDOUT; + break; + } + } + } + } + ret = fd_read (fd, dlbuf, rdsize, tmout); + + if (progress_interactive && ret < 0 && errno == ETIMEDOUT) + ret = 0; /* interactive timeout, handled above */ + else if (ret <= 0) + break; /* EOF or read error */ + + if (progress || opt.limit_rate || elapsed) + { + ptimer_measure (timer); + if (ret > 0) + last_successful_read_tm = ptimer_read (timer); + } + + if (ret > 0) + { + int write_res; + + sum_read += ret; + +#ifdef HAVE_LIBZ + if (gzbuf != NULL) + { + int err; + int towrite; + + /* Write original data to WARC file */ + write_res = write_data (NULL, out2, dlbuf, ret, NULL, NULL); + if (write_res < 0) + { + ret = write_res; + goto out; + } + + gzstream.avail_in = ret; + gzstream.next_in = (unsigned char *) dlbuf; + + do + { + gzstream.avail_out = gzbufsize; + gzstream.next_out = (unsigned char *) gzbuf; + + err = inflate (&gzstream, Z_NO_FLUSH); + + switch (err) + { + case Z_MEM_ERROR: + errno = ENOMEM; + ret = -1; + goto out; + case Z_NEED_DICT: + case Z_DATA_ERROR: + errno = EINVAL; + ret = -1; + goto out; + case Z_STREAM_END: + if (exact && sum_read != toread) + { + DEBUGP(("zlib stream ended unexpectedly after %"PRId64"/%"PRId64 + " bytes\n", sum_read, toread)); + } + } + + towrite = gzbufsize - gzstream.avail_out; + write_res = write_data (out, NULL, gzbuf, towrite, &skip, + &sum_written); + if (write_res < 0) + { + ret = write_res; + goto out; + } + } + while (gzstream.avail_out == 0); + } + else +#endif + { + write_res = write_data (out, out2, dlbuf, ret, &skip, + &sum_written); + if (write_res < 0) + { + ret = write_res; + goto out; + } + } + + if (chunked) + { + remaining_chunk_size -= ret; + if (remaining_chunk_size == 0) + { + char *line = fd_read_line (fd); + if (line == NULL) + { + ret = -1; + break; + } + else + { + if (out2 != NULL) + fwrite (line, 1, strlen (line), out2); + xfree (line); + } + } + } + } + + if (opt.limit_rate) + limit_bandwidth (ret, timer); + + if (progress) + progress_update (progress, ret, ptimer_read (timer)); +#ifdef WINDOWS + if (toread > 0 && opt.show_progress) + ws_percenttitle (100.0 * + (startpos + sum_read) / (startpos + toread)); +#endif + } + if (ret < -1) + ret = -1; + + out: + if (progress) + progress_finish (progress, ptimer_read (timer)); + + if (timer) + { + if (elapsed) + *elapsed = ptimer_read (timer); + ptimer_destroy (timer); + } + +#ifdef HAVE_LIBZ + if (gzbuf != NULL) + { + int err = inflateEnd (&gzstream); + if (ret >= 0) + { + /* with compression enabled, ret must be 0 if successful */ + if (err == Z_OK) + ret = 0; + else + { + errno = EINVAL; + ret = -1; + } + } + xfree (gzbuf); + + if (gzstream.total_in != (uLong) sum_read) + { + DEBUGP(("zlib read size differs from raw read size (%lu/%"PRId64")\n", + gzstream.total_in, sum_read)); + } + } +#endif + + if (qtyread) + *qtyread += sum_read; + if (qtywritten) + *qtywritten += sum_written; + + xfree (dlbuf); + + return ret; +} + +/* Read a hunk of data from FD, up until a terminator. The hunk is + limited by whatever the TERMINATOR callback chooses as its + terminator. For example, if terminator stops at newline, the hunk + will consist of a line of data; if terminator stops at two + newlines, it can be used to read the head of an HTTP response. + Upon determining the boundary, the function returns the data (up to + the terminator) in malloc-allocated storage. + + In case of read error, NULL is returned. In case of EOF and no + data read, NULL is returned and errno set to 0. In case of having + read some data, but encountering EOF before seeing the terminator, + the data that has been read is returned, but it will (obviously) + not contain the terminator. + + The TERMINATOR function is called with three arguments: the + beginning of the data read so far, the beginning of the current + block of peeked-at data, and the length of the current block. + Depending on its needs, the function is free to choose whether to + analyze all data or just the newly arrived data. If TERMINATOR + returns NULL, it means that the terminator has not been seen. + Otherwise it should return a pointer to the charactre immediately + following the terminator. + + The idea is to be able to read a line of input, or otherwise a hunk + of text, such as the head of an HTTP request, without crossing the + boundary, so that the next call to fd_read etc. reads the data + after the hunk. To achieve that, this function does the following: + + 1. Peek at incoming data. + + 2. Determine whether the peeked data, along with the previously + read data, includes the terminator. + + 2a. If yes, read the data until the end of the terminator, and + exit. + + 2b. If no, read the peeked data and goto 1. + + The function is careful to assume as little as possible about the + implementation of peeking. For example, every peek is followed by + a read. If the read returns a different amount of data, the + process is retried until all data arrives safely. + + SIZEHINT is the buffer size sufficient to hold all the data in the + typical case (it is used as the initial buffer size). MAXSIZE is + the maximum amount of memory this function is allowed to allocate, + or 0 if no upper limit is to be enforced. + + This function should be used as a building block for other + functions -- see fd_read_line as a simple example. */ + +char * +fd_read_hunk (int fd, hunk_terminator_t terminator, long sizehint, long maxsize) +{ + long bufsize = sizehint; + char *hunk = xmalloc (bufsize); + int tail = 0; /* tail position in HUNK */ + + assert (!maxsize || maxsize >= bufsize); + + while (1) + { + const char *end; + int pklen, rdlen, remain; + + /* First, peek at the available data. */ + + pklen = fd_peek (fd, hunk + tail, bufsize - 1 - tail, -1); + if (pklen < 0) + { + xfree (hunk); + return NULL; + } + end = terminator (hunk, hunk + tail, pklen); + if (end) + { + /* The data contains the terminator: we'll drain the data up + to the end of the terminator. */ + remain = end - (hunk + tail); + assert (remain >= 0); + if (remain == 0) + { + /* No more data needs to be read. */ + hunk[tail] = '\0'; + return hunk; + } + if (bufsize - 1 < tail + remain) + { + bufsize = tail + remain + 1; + hunk = xrealloc (hunk, bufsize); + } + } + else + /* No terminator: simply read the data we know is (or should + be) available. */ + remain = pklen; + + /* Now, read the data. Note that we make no assumptions about + how much data we'll get. (Some TCP stacks are notorious for + read returning less data than the previous MSG_PEEK.) */ + + rdlen = fd_read (fd, hunk + tail, remain, 0); + if (rdlen < 0) + { + xfree (hunk); + return NULL; + } + tail += rdlen; + hunk[tail] = '\0'; + + if (rdlen == 0) + { + if (tail == 0) + { + /* EOF without anything having been read */ + xfree (hunk); + errno = 0; + return NULL; + } + else + /* EOF seen: return the data we've read. */ + return hunk; + } + if (end && rdlen == remain) + /* The terminator was seen and the remaining data drained -- + we got what we came for. */ + return hunk; + + /* Keep looping until all the data arrives. */ + + if (tail == bufsize - 1) + { + /* Double the buffer size, but refuse to allocate more than + MAXSIZE bytes. */ + if (maxsize && bufsize >= maxsize) + { + xfree (hunk); + errno = ENOMEM; + return NULL; + } + bufsize <<= 1; + if (maxsize && bufsize > maxsize) + bufsize = maxsize; + hunk = xrealloc (hunk, bufsize); + } + } +} + +static const char * +line_terminator (const char *start _GL_UNUSED, const char *peeked, int peeklen) +{ + const char *p = memchr (peeked, '\n', peeklen); + if (p) + /* p+1 because the line must include '\n' */ + return p + 1; + return NULL; +} + +/* The maximum size of the single line we agree to accept. This is + not meant to impose an arbitrary limit, but to protect the user + from Wget slurping up available memory upon encountering malicious + or buggy server output. Define it to 0 to remove the limit. */ +#define FD_READ_LINE_MAX 4096 + +/* Read one line from FD and return it. The line is allocated using + malloc, but is never larger than FD_READ_LINE_MAX. + + If an error occurs, or if no data can be read, NULL is returned. + In the former case errno indicates the error condition, and in the + latter case, errno is NULL. */ + +char * +fd_read_line (int fd) +{ + return fd_read_hunk (fd, line_terminator, 128, FD_READ_LINE_MAX); +} + +/* Return a printed representation of the download rate, along with + the units appropriate for the download speed. */ + +const char * +retr_rate (wgint bytes, double secs) +{ + static char res[20]; + static const char *rate_names[] = {"B/s", "KB/s", "MB/s", "GB/s" }; + static const char *rate_names_bits[] = {"b/s", "Kb/s", "Mb/s", "Gb/s" }; + int units; + + double dlrate = calc_rate (bytes, secs, &units); + /* Use more digits for smaller numbers (regardless of unit used), + e.g. "1022", "247", "12.5", "2.38". */ + snprintf (res, sizeof(res), "%.*f %s", + dlrate >= 99.95 ? 0 : dlrate >= 9.995 ? 1 : 2, + dlrate, !opt.report_bps ? rate_names[units]: rate_names_bits[units]); + + return res; +} + +/* Calculate the download rate and trim it as appropriate for the + speed. Appropriate means that if rate is greater than 1K/s, + kilobytes are used, and if rate is greater than 1MB/s, megabytes + are used. + + UNITS is zero for B/s, one for KB/s, two for MB/s, and three for + GB/s. */ + +double +calc_rate (wgint bytes, double secs, int *units) +{ + double dlrate; + double bibyte; + + if (!opt.report_bps) + bibyte = 1024.0; + else + bibyte = 1000.0; + + if (secs == 0) + /* If elapsed time is exactly zero, it means we're under the + resolution of the timer. This can easily happen on systems + that use time() for the timer. Since the interval lies between + 0 and the timer's resolution, assume half the resolution. */ + secs = ptimer_resolution () / 2.0; + + dlrate = secs ? convert_to_bits (bytes) / secs : 0; + if (dlrate < bibyte) + *units = 0; + else if (dlrate < (bibyte * bibyte)) + *units = 1, dlrate /= bibyte; + else if (dlrate < (bibyte * bibyte * bibyte)) + *units = 2, dlrate /= (bibyte * bibyte); + else if (dlrate < (bibyte * bibyte * bibyte * bibyte)) + *units = 3, dlrate /= (bibyte * bibyte * bibyte); + else { + *units = 4, dlrate /= (bibyte * bibyte * bibyte * bibyte); + if (dlrate > 99.99) + dlrate = 99.99; // upper limit 99.99TB/s + } + + return dlrate; +} + + +#define SUSPEND_METHOD do { \ + method_suspended = true; \ + saved_body_data = opt.body_data; \ + saved_body_file_name = opt.body_file; \ + saved_method = opt.method; \ + opt.body_data = NULL; \ + opt.body_file = NULL; \ + opt.method = NULL; \ +} while (0) + +#define RESTORE_METHOD do { \ + if (method_suspended) \ + { \ + opt.body_data = saved_body_data; \ + opt.body_file = saved_body_file_name; \ + opt.method = saved_method; \ + method_suspended = false; \ + } \ +} while (0) + +static char *getproxy (struct url *); + +/* Retrieve the given URL. Decides which loop to call -- HTTP, FTP, + FTP, proxy, etc. */ + +/* #### This function should be rewritten so it doesn't return from + multiple points. */ + +uerr_t +retrieve_url (struct url * orig_parsed, const char *origurl, char **file, + char **newloc, const char *refurl, int *dt, bool recursive, + struct iri *iri, bool register_status) +{ + uerr_t result; + char *url; + bool location_changed; + bool iri_fallbacked = 0; + int dummy; + char *mynewloc, *proxy; + struct url *u = orig_parsed, *proxy_url; + int up_error_code; /* url parse error code */ + char *local_file = NULL; + int redirection_count = 0; + + bool method_suspended = false; + char *saved_body_data = NULL; + char *saved_method = NULL; + char *saved_body_file_name = NULL; + + /* If dt is NULL, use local storage. */ + if (!dt) + { + dt = &dummy; + dummy = 0; + } + url = xstrdup (origurl); + if (newloc) + *newloc = NULL; + if (file) + *file = NULL; + + if (!refurl) + refurl = opt.referer; + + redirected: + /* (also for IRI fallbacking) */ + + result = NOCONERROR; + mynewloc = NULL; + xfree(local_file); + proxy_url = NULL; + + proxy = getproxy (u); + if (proxy) + { + struct iri *pi = iri_new (); + set_uri_encoding (pi, opt.locale, true); + pi->utf8_encode = false; + + /* Parse the proxy URL. */ + proxy_url = url_parse (proxy, &up_error_code, pi, true); + if (!proxy_url) + { + char *error = url_error (proxy, up_error_code); + logprintf (LOG_NOTQUIET, _("Error parsing proxy URL %s: %s.\n"), + proxy, error); + xfree (url); + xfree (error); + xfree (proxy); + iri_free (pi); + RESTORE_METHOD; + result = PROXERR; + if (orig_parsed != u) + url_free (u); + goto bail; + } + if (proxy_url->scheme != SCHEME_HTTP && proxy_url->scheme != u->scheme) + { + logprintf (LOG_NOTQUIET, _("Error in proxy URL %s: Must be HTTP.\n"), proxy); + url_free (proxy_url); + xfree (url); + xfree (proxy); + iri_free (pi); + RESTORE_METHOD; + result = PROXERR; + if (orig_parsed != u) + url_free (u); + goto bail; + } + iri_free(pi); + xfree (proxy); + } + + if (u->scheme == SCHEME_HTTP +#ifdef HAVE_SSL + || u->scheme == SCHEME_HTTPS +#endif + || (proxy_url && proxy_url->scheme == SCHEME_HTTP)) + { +#ifdef HAVE_HSTS +#ifdef TESTING + /* we don't link against main.o when we're testing */ + hsts_store_t hsts_store = NULL; +#else + extern hsts_store_t hsts_store; +#endif + + if (opt.hsts && hsts_store) + { + if (hsts_match (hsts_store, u)) + logprintf (LOG_VERBOSE, "URL transformed to HTTPS due to an HSTS policy\n"); + } +#endif + result = http_loop (u, orig_parsed, &mynewloc, &local_file, refurl, dt, + proxy_url, iri); + } + else if (u->scheme == SCHEME_FTP +#ifdef HAVE_SSL + || u->scheme == SCHEME_FTPS +#endif + ) + { + /* If this is a redirection, temporarily turn off opt.ftp_glob + and opt.recursive, both being undesirable when following + redirects. */ + bool oldrec = recursive, glob = opt.ftp_glob; + if (redirection_count) + oldrec = glob = false; + + result = ftp_loop (u, orig_parsed, &local_file, dt, proxy_url, + recursive, glob); + recursive = oldrec; + + /* There is a possibility of having HTTP being redirected to + FTP. In these cases we must decide whether the text is HTML + according to the suffix. The HTML suffixes are `.html', + `.htm' and a few others, case-insensitive. */ + if (redirection_count && local_file && (u->scheme == SCHEME_FTP +#ifdef HAVE_SSL + || u->scheme == SCHEME_FTPS +#endif + )) + { + if (has_html_suffix_p (local_file)) + *dt |= TEXTHTML; + } + } + + if (proxy_url) + { + url_free (proxy_url); + proxy_url = NULL; + } + + location_changed = (result == NEWLOCATION || result == NEWLOCATION_KEEP_POST); + if (location_changed) + { + char *construced_newloc; + struct url *newloc_parsed; + + assert (mynewloc != NULL); + + xfree (local_file); + + /* The HTTP specs only allow absolute URLs to appear in + redirects, but a ton of boneheaded webservers and CGIs out + there break the rules and use relative URLs, and popular + browsers are lenient about this, so wget should be too. */ + construced_newloc = uri_merge (url, mynewloc ? mynewloc : ""); + xfree (mynewloc); + mynewloc = construced_newloc; + +#ifdef ENABLE_IRI + /* Reset UTF-8 encoding state, set the URI encoding and reset + the content encoding. */ + iri->utf8_encode = opt.enable_iri; + if (opt.encoding_remote) + set_uri_encoding (iri, opt.encoding_remote, true); + set_content_encoding (iri, NULL); + xfree (iri->orig_url); +#endif + + /* Now, see if this new location makes sense. */ + newloc_parsed = url_parse (mynewloc, &up_error_code, iri, true); + if (!newloc_parsed) + { + char *error = url_error (mynewloc, up_error_code); + logprintf (LOG_NOTQUIET, "%s: %s.\n", escnonprint_uri (mynewloc), + error); + if (orig_parsed != u) + { + url_free (u); + } + xfree (url); + xfree (mynewloc); + xfree (error); + RESTORE_METHOD; + goto bail; + } + + /* Now mynewloc will become newloc_parsed->url, because if the + Location contained relative paths like .././something, we + don't want that propagating as url. */ + xfree (mynewloc); + mynewloc = xstrdup (newloc_parsed->url); + + /* Check for max. number of redirections. */ + if (++redirection_count > opt.max_redirect) + { + logprintf (LOG_NOTQUIET, _("%d redirections exceeded.\n"), + opt.max_redirect); + url_free (newloc_parsed); + if (orig_parsed != u) + { + url_free (u); + } + xfree (url); + xfree (mynewloc); + RESTORE_METHOD; + result = WRONGCODE; + goto bail; + } + + xfree (url); + url = mynewloc; + if (orig_parsed != u) + { + url_free (u); + } + u = newloc_parsed; + + /* If we're being redirected from POST, and we received a + redirect code different than 307, we don't want to POST + again. Many requests answer POST with a redirection to an + index page; that redirection is clearly a GET. We "suspend" + POST data for the duration of the redirections, and restore + it when we're done. + + RFC2616 HTTP/1.1 introduces code 307 Temporary Redirect + specifically to preserve the method of the request. + */ + if (result != NEWLOCATION_KEEP_POST && !method_suspended) + SUSPEND_METHOD; + + goto redirected; + } + else + { + xfree(mynewloc); + } + + /* Try to not encode in UTF-8 if fetching failed */ + if (!(*dt & RETROKF) && iri->utf8_encode) + { + iri->utf8_encode = false; + if (orig_parsed != u) + { + url_free (u); + } + u = url_parse (origurl, NULL, iri, true); + if (u) + { + if (strcmp(u->url, orig_parsed->url)) + { + DEBUGP (("[IRI fallbacking to non-utf8 for %s\n", quote (url))); + xfree (url); + url = xstrdup (u->url); + iri_fallbacked = 1; + goto redirected; + } + else + DEBUGP (("[Needn't fallback to non-utf8 for %s\n", quote (url))); + } + else + DEBUGP (("[Couldn't fallback to non-utf8 for %s\n", quote (url))); + } + + if (local_file && u && (*dt & RETROKF || opt.content_on_error)) + { + register_download (u->url, local_file); + + if (!opt.spider && redirection_count && 0 != strcmp (origurl, u->url)) + register_redirection (origurl, u->url); + + if (*dt & TEXTHTML) + register_html (local_file); + + if (*dt & TEXTCSS) + register_css (local_file); + } + + if (file) + *file = local_file ? local_file : NULL; + else + xfree (local_file); + + if (orig_parsed != u) + url_free (u); + + if (redirection_count || iri_fallbacked) + { + if (newloc) + *newloc = url; + else + xfree (url); + } + else + { + if (newloc) + *newloc = NULL; + xfree (url); + } + + RESTORE_METHOD; + +bail: + if (register_status) + inform_exit_status (result); + + return result; +} + +/* Find the URLs in the file and call retrieve_url() for each of them. + If HTML is true, treat the file as HTML, and construct the URLs + accordingly. + + If opt.recursive is set, call retrieve_tree() for each file. */ + +uerr_t +retrieve_from_file (const char *file, bool html, int *count) +{ + uerr_t status; + struct urlpos *url_list, *cur_url; + struct iri *iri = iri_new(); + + char *input_file, *url_file = NULL; + const char *url = file; + + status = RETROK; /* Suppose everything is OK. */ + *count = 0; /* Reset the URL count. */ + + /* sXXXav : Assume filename and links in the file are in the locale */ + set_uri_encoding (iri, opt.locale, true); + set_content_encoding (iri, opt.locale); + + if (url_valid_scheme (url)) + { + int dt,url_err; + struct url *url_parsed = url_parse (url, &url_err, iri, true); + if (!url_parsed) + { + char *error = url_error (url, url_err); + logprintf (LOG_NOTQUIET, "%s: %s.\n", url, error); + xfree (error); + iri_free (iri); + return URLERROR; + } + + if (!opt.base_href) + opt.base_href = xstrdup (url); + + status = retrieve_url (url_parsed, url, &url_file, NULL, NULL, &dt, + false, iri, true); + url_free (url_parsed); + + if (!url_file || (status != RETROK)) + return status; + + if (dt & TEXTHTML) + html = true; + +#ifdef ENABLE_IRI + /* If we have a found a content encoding, use it. + * ( == is okay, because we're checking for identical object) */ + if (iri->content_encoding != opt.locale) + set_uri_encoding (iri, iri->content_encoding, false); +#endif + + /* Reset UTF-8 encode status */ + iri->utf8_encode = opt.enable_iri; + xfree (iri->orig_url); + + input_file = url_file; + } + else + input_file = (char *) file; + + url_list = (html ? get_urls_html (input_file, NULL, NULL, iri) + : get_urls_file (input_file)); + + xfree (url_file); + + for (cur_url = url_list; cur_url; cur_url = cur_url->next, ++*count) + { + char *filename = NULL, *new_file = NULL, *proxy; + int dt = 0; + struct iri *tmpiri = iri_dup (iri); + struct url *parsed_url = NULL; + + if (cur_url->ignore_when_downloading) + continue; + + if (opt.quota && total_downloaded_bytes > opt.quota) + { + status = QUOTEXC; + break; + } + + parsed_url = url_parse (cur_url->url->url, NULL, tmpiri, true); + + proxy = getproxy (cur_url->url); + if ((opt.recursive || opt.page_requisites) + && ((cur_url->url->scheme != SCHEME_FTP +#ifdef HAVE_SSL + && cur_url->url->scheme != SCHEME_FTPS +#endif + ) || proxy)) + { + int old_follow_ftp = opt.follow_ftp; + + /* Turn opt.follow_ftp on in case of recursive FTP retrieval */ + if (cur_url->url->scheme == SCHEME_FTP +#ifdef HAVE_SSL + || cur_url->url->scheme == SCHEME_FTPS +#endif + ) + opt.follow_ftp = 1; + + status = retrieve_tree (parsed_url ? parsed_url : cur_url->url, + tmpiri); + + opt.follow_ftp = old_follow_ftp; + } + else + status = retrieve_url (parsed_url ? parsed_url : cur_url->url, + cur_url->url->url, &filename, + &new_file, NULL, &dt, opt.recursive, tmpiri, + true); + xfree (proxy); + + if (parsed_url) + url_free (parsed_url); + + if (filename && opt.delete_after && file_exists_p (filename, NULL)) + { + DEBUGP (("\ +Removing file due to --delete-after in retrieve_from_file():\n")); + logprintf (LOG_VERBOSE, _("Removing %s.\n"), filename); + if (unlink (filename)) + logprintf (LOG_NOTQUIET, "Failed to unlink %s: (%d) %s\n", filename, errno, strerror (errno)); + dt &= ~RETROKF; + } + + xfree (new_file); + xfree (filename); + iri_free (tmpiri); + } + + /* Free the linked list of URL-s. */ + free_urlpos (url_list); + + iri_free (iri); + + return status; +} + +/* Print `giving up', or `retrying', depending on the impending + action. N1 and N2 are the attempt number and the attempt limit. */ +void +printwhat (int n1, int n2) +{ + logputs (LOG_VERBOSE, (n1 == n2) ? _("Giving up.\n\n") : _("Retrying.\n\n")); +} + +/* If opt.wait or opt.waitretry are specified, and if certain + conditions are met, sleep the appropriate number of seconds. See + the documentation of --wait and --waitretry for more information. + + COUNT is the count of current retrieval, beginning with 1. */ + +void +sleep_between_retrievals (int count) +{ + static bool first_retrieval = true; + + if (first_retrieval) + { + /* Don't sleep before the very first retrieval. */ + first_retrieval = false; + return; + } + + if (opt.waitretry && count > 1) + { + /* If opt.waitretry is specified and this is a retry, wait for + COUNT-1 number of seconds, or for opt.waitretry seconds. */ + if (count <= opt.waitretry) + xsleep (count - 1); + else + xsleep (opt.waitretry); + } + else if (opt.wait) + { + if (!opt.random_wait || count > 1) + /* If random-wait is not specified, or if we are sleeping + between retries of the same download, sleep the fixed + interval. */ + xsleep (opt.wait); + else + { + /* Sleep a random amount of time averaging in opt.wait + seconds. The sleeping amount ranges from 0.5*opt.wait to + 1.5*opt.wait. */ + double waitsecs = (0.5 + random_float ()) * opt.wait; + DEBUGP (("sleep_between_retrievals: avg=%f,sleep=%f\n", + opt.wait, waitsecs)); + xsleep (waitsecs); + } + } +} + +/* Free the linked list of urlpos. */ +void +free_urlpos (struct urlpos *l) +{ + while (l) + { + struct urlpos *next = l->next; + if (l->url) + url_free (l->url); + xfree (l->local_name); + xfree (l); + l = next; + } +} + +/* Rotate FNAME opt.backups times */ +void +rotate_backups(const char *fname) +{ +#ifdef __VMS +# define SEP "_" +# define AVS ";*" /* All-version suffix. */ +# define AVSL (sizeof (AVS) - 1) +#else +# define SEP "." +# define AVSL 0 +#endif +#define FILE_BUF_SIZE 1024 + + /* avoid alloca() here */ + char from[FILE_BUF_SIZE], to[FILE_BUF_SIZE]; + struct stat sb; + bool overflow; + int i; + + if (stat (fname, &sb) == 0) + if (S_ISREG (sb.st_mode) == 0) + return; + + for (i = opt.backups; i > 1; i--) + { +#ifdef VMS + /* Delete (all versions of) any existing max-suffix file, to avoid + * creating multiple versions of it. (On VMS, rename() will + * create a new version of an existing destination file, not + * destroy/overwrite it.) + */ + if (i == opt.backups) + { + if (((unsigned) snprintf (to, sizeof (to), "%s%s%d%s", fname, SEP, i, AVS)) >= sizeof (to)) + logprintf (LOG_NOTQUIET, "Failed to delete %s: File name truncation\n", to); + else + delete (to); + } +#endif + overflow = (unsigned) snprintf (to, FILE_BUF_SIZE, "%s%s%d", fname, SEP, i) >= FILE_BUF_SIZE; + overflow |= (unsigned) snprintf (from, FILE_BUF_SIZE, "%s%s%d", fname, SEP, i - 1) >= FILE_BUF_SIZE; + + if (overflow) + errno = ENAMETOOLONG; + if (overflow || rename (from, to)) + { + // The original file may not exist. In which case rename() will + // return ENOENT. This is not a real error. We could make this better + // by calling stat() first and making sure that the file exists. + if (errno != ENOENT) + logprintf (LOG_NOTQUIET, "Failed to rename %s to %s: (%d) %s\n", + from, to, errno, strerror (errno)); + } + } + + overflow = (unsigned) snprintf (to, FILE_BUF_SIZE, "%s%s%d", fname, SEP, 1) >= FILE_BUF_SIZE; + if (overflow) + errno = ENAMETOOLONG; + if (overflow || rename(fname, to)) + { + if (errno != ENOENT) + logprintf (LOG_NOTQUIET, "Failed to rename %s to %s: (%d) %s\n", + from, to, errno, strerror (errno)); + } + +#undef FILE_BUF_SIZE +} + +static bool no_proxy_match (const char *, const char **); + +/* Return the URL of the proxy appropriate for url U. */ + +static char * +getproxy (struct url *u) +{ + char *proxy = NULL; + char *rewritten_url; + + if (!opt.use_proxy) + return NULL; + if (no_proxy_match (u->host, (const char **)opt.no_proxy)) + return NULL; + + switch (u->scheme) + { + case SCHEME_HTTP: + proxy = opt.http_proxy ? opt.http_proxy : getenv ("http_proxy"); + break; +#ifdef HAVE_SSL + case SCHEME_HTTPS: + proxy = opt.https_proxy ? opt.https_proxy : getenv ("https_proxy"); + break; + case SCHEME_FTPS: + proxy = opt.ftp_proxy ? opt.ftp_proxy : getenv ("ftps_proxy"); + break; +#endif + case SCHEME_FTP: + proxy = opt.ftp_proxy ? opt.ftp_proxy : getenv ("ftp_proxy"); + break; + case SCHEME_INVALID: + break; + } + if (!proxy || !*proxy) + return NULL; + + /* Handle shorthands. `rewritten_storage' is a kludge to allow + getproxy() to return static storage. */ + rewritten_url = rewrite_shorthand_url (proxy); + if (rewritten_url) + return rewritten_url; + + return strdup(proxy); +} + +/* Returns true if URL would be downloaded through a proxy. */ + +bool +url_uses_proxy (struct url * u) +{ + bool ret; + char *proxy; + + if (!u) + return false; + proxy = getproxy (u); + ret = proxy != NULL; + xfree (proxy); + return ret; +} + +/* Should a host be accessed through proxy, concerning no_proxy? */ +static bool +no_proxy_match (const char *host, const char **no_proxy) +{ + if (!no_proxy) + return false; + else + return sufmatch (no_proxy, host); +} + +/* Set the file parameter to point to the local file string. */ +void +set_local_file (const char **file, const char *default_file) +{ + if (opt.output_document) + { + if (output_stream_regular) + *file = opt.output_document; + } + else + *file = default_file; +} + +/* Return true for an input file's own URL, false otherwise. */ +bool +input_file_url (const char *input_file) +{ + static bool first = true; + + if (input_file + && url_has_scheme (input_file) + && first) + { + first = false; + return true; + } + else + return false; +} |