X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=daemon%2Fproto.c;h=88e2d28c793739a19cd6b46d990586ecdd087b85;hp=2231037b61981a8cce00144dd1220594593e14c1;hb=5ce759bfdc70c97121ef34ab4d5c918d568f2474;hpb=55355491c5ad2535b99a31ec81241f7f9f92177e diff --git a/daemon/proto.c b/daemon/proto.c index 2231037..88e2d28 100644 --- a/daemon/proto.c +++ b/daemon/proto.c @@ -1,5 +1,5 @@ /* libguestfs - the guestfsd daemon - * Copyright (C) 2009 Red Hat Inc. + * Copyright (C) 2009-2011 Red Hat Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -22,23 +22,57 @@ #include #include #include +#include +#include #include #include #include /* defines MIN */ #include +#include #include #include +#ifdef HAVE_WINDOWS_H +#include +#endif + #include "c-ctype.h" #include "ignore-value.h" #include "daemon.h" -#include "../src/guestfs_protocol.h" +#include "guestfs_protocol.h" +#include "errnostring.h" /* The message currently being processed. */ int proc_nr; int serial; +/* Hint for implementing progress messages for uploaded/incoming data. + * The caller sets this to a value > 0 if it knows or can estimate how + * much data will be sent (this is not always known, eg. for uploads + * coming from a pipe). If this is known then we can emit progress + * messages as we write the data. + */ +uint64_t progress_hint; + +/* Optional arguments bitmask. Caller sets this to indicate which + * optional arguments in the guestfs__args structure are + * meaningful. Optional arguments not covered by the bitmask are set + * to arbitrary values and the daemon should ignore them. If the + * bitmask has bits set that the daemon doesn't understand, then the + * whole call is rejected early in processing. + */ +uint64_t optargs_bitmask; + +/* Time at which we received the current request. */ +static struct timeval start_t; + +/* Time at which the last progress notification was sent. */ +static struct timeval last_progress_t; + +/* Counts the number of progress notifications sent during this call. */ +static int count_progress; + /* The daemon communications socket. */ static int sock; @@ -50,18 +84,10 @@ main_loop (int _sock) char lenbuf[4]; uint32_t len; struct guestfs_message_header hdr; - struct timeval start_t, end_t; - int64_t start_us, end_us, elapsed_us; sock = _sock; for (;;) { - /* Most common errors are leaked memory and leaked file descriptors, - * so run this between each command: - */ - if (verbose && 0) - ignore_value (system ("ls -l /proc/self/fd")); - /* Read the length word. */ if (xread (sock, lenbuf, 4) == -1) exit (EXIT_FAILURE); @@ -70,6 +96,11 @@ main_loop (int _sock) xdr_u_int (&xdr, &len); xdr_destroy (&xdr); + if (verbose) + fprintf (stderr, + "guestfsd: main_loop: new request, len 0x%" PRIx32 "\n", + len); + if (len > GUESTFS_MESSAGE_MAX) { fprintf (stderr, "guestfsd: incoming message is too long (%u bytes)\n", len); @@ -108,9 +139,9 @@ main_loop (int _sock) } #endif - /* In verbose mode, display the time taken to run each command. */ - if (verbose) - gettimeofday (&start_t, NULL); + gettimeofday (&start_t, NULL); + last_progress_t = start_t; + count_progress = 0; /* Decode the message header. */ xdrmem_create (&xdr, buf, len, XDR_DECODE); @@ -137,20 +168,37 @@ main_loop (int _sock) goto cont; } - /* Now start to process this message. */ proc_nr = hdr.proc; serial = hdr.serial; + progress_hint = hdr.progress_hint; + optargs_bitmask = hdr.optargs_bitmask; + + /* Clear errors before we call the stub functions. This is just + * to ensure that we can accurately report errors in cases where + * error handling paths don't set errno correctly. + */ + errno = 0; +#ifdef WIN32 + SetLastError (0); + WSASetLastError (0); +#endif + + /* Now start to process this message. */ dispatch_incoming_message (&xdr); /* Note that dispatch_incoming_message will also send a reply. */ /* In verbose mode, display the time taken to run each command. */ if (verbose) { + struct timeval end_t; gettimeofday (&end_t, NULL); + int64_t start_us, end_us, elapsed_us; start_us = (int64_t) start_t.tv_sec * 1000000 + start_t.tv_usec; end_us = (int64_t) end_t.tv_sec * 1000000 + end_t.tv_usec; elapsed_us = end_us - start_us; - fprintf (stderr, "proc %d (%s) took %d.%02d seconds\n", + + fprintf (stderr, + "guestfsd: main_loop: proc %d (%s) took %d.%02d seconds\n", proc_nr, proc_nr >= 0 && proc_nr < GUESTFS_PROC_NR_PROCS ? function_names[proc_nr] : "UNKNOWN PROCEDURE", @@ -164,7 +212,7 @@ main_loop (int _sock) } } -static void send_error (const char *msg); +static void send_error (int errnum, const char *msg); void reply_with_error (const char *fs, ...) @@ -176,16 +224,15 @@ reply_with_error (const char *fs, ...) vsnprintf (err, sizeof err, fs, args); va_end (args); - send_error (err); + send_error (0, err); } void -reply_with_perror (const char *fs, ...) +reply_with_perror_errno (int err, const char *fs, ...) { char buf1[GUESTFS_ERROR_LEN]; char buf2[GUESTFS_ERROR_LEN]; va_list args; - int err = errno; va_start (args, fs); vsnprintf (buf1, sizeof buf1, fs, args); @@ -193,11 +240,11 @@ reply_with_perror (const char *fs, ...) snprintf (buf2, sizeof buf2, "%s: %s", buf1, strerror (err)); - send_error (buf2); + send_error (err, buf2); } static void -send_error (const char *msg) +send_error (int errnum, const char *msg) { XDR xdr; char buf[GUESTFS_ERROR_LEN + 200]; @@ -222,6 +269,11 @@ send_error (const char *msg) exit (EXIT_FAILURE); } + /* These strings are not going to be freed. We just cast them + * to (char *) because they are defined that way in the XDR structs. + */ + err.errno_string = + (char *) (errnum > 0 ? guestfs___errno_to_string (errnum) : ""); err.error_message = (char *) msg; if (!xdr_guestfs_message_error (&xdr, &err)) { @@ -237,11 +289,11 @@ send_error (const char *msg) xdr_destroy (&xdr); if (xwrite (sock, lenbuf, 4) == -1) { - fprintf (stderr, "xwrite failed\n"); + fprintf (stderr, "guestfsd: xwrite failed\n"); exit (EXIT_FAILURE); } if (xwrite (sock, buf, len) == -1) { - fprintf (stderr, "xwrite failed\n"); + fprintf (stderr, "guestfsd: xwrite failed\n"); exit (EXIT_FAILURE); } } @@ -275,7 +327,7 @@ reply (xdrproc_t xdrp, char *ret) * we want to return an error message instead. (RHBZ#509597). */ if (!(*xdrp) (&xdr, ret)) { - reply_with_perror ("guestfsd: failed to encode reply body\n"); + reply_with_error ("guestfsd: failed to encode reply body\n(maybe the reply exceeds the maximum message size in the protocol?)"); xdr_destroy (&xdr); return; } @@ -289,11 +341,11 @@ reply (xdrproc_t xdrp, char *ret) xdr_destroy (&xdr); if (xwrite (sock, lenbuf, 4) == -1) { - fprintf (stderr, "xwrite failed\n"); + fprintf (stderr, "guestfsd: xwrite failed\n"); exit (EXIT_FAILURE); } if (xwrite (sock, buf, len) == -1) { - fprintf (stderr, "xwrite failed\n"); + fprintf (stderr, "guestfsd: xwrite failed\n"); exit (EXIT_FAILURE); } } @@ -310,6 +362,9 @@ receive_file (receive_cb cb, void *opaque) uint32_t len; for (;;) { + if (verbose) + fprintf (stderr, "guestfsd: receive_file: reading length word\n"); + /* Read the length word. */ if (xread (sock, lenbuf, 4) == -1) exit (EXIT_FAILURE); @@ -347,32 +402,49 @@ receive_file (receive_cb cb, void *opaque) free (buf); if (verbose) - printf ("receive_file: got chunk: cancel = %d, len = %d, buf = %p\n", - chunk.cancel, chunk.data.data_len, chunk.data.data_val); + fprintf (stderr, + "guestfsd: receive_file: got chunk: cancel = 0x%x, len = %d, buf = %p\n", + chunk.cancel, chunk.data.data_len, chunk.data.data_val); + + if (chunk.cancel != 0 && chunk.cancel != 1) { + fprintf (stderr, + "guestfsd: receive_file: chunk.cancel != [0|1] ... " + "continuing even though we have probably lost synchronization with the library\n"); + return -1; + } if (chunk.cancel) { - fprintf (stderr, "receive_file: received cancellation from library\n"); + if (verbose) + fprintf (stderr, + "guestfsd: receive_file: received cancellation from library\n"); xdr_free ((xdrproc_t) xdr_guestfs_chunk, (char *) &chunk); return -2; } if (chunk.data.data_len == 0) { + if (verbose) + fprintf (stderr, + "guestfsd: receive_file: end of file, leaving function\n"); xdr_free ((xdrproc_t) xdr_guestfs_chunk, (char *) &chunk); return 0; /* end of file */ } + /* Note that the callback can generate progress messages. */ if (cb) r = cb (opaque, chunk.data.data_val, chunk.data.data_len); else r = 0; xdr_free ((xdrproc_t) xdr_guestfs_chunk, (char *) &chunk); - if (r == -1) /* write error */ + if (r == -1) { /* write error */ + if (verbose) + fprintf (stderr, "guestfsd: receive_file: write error\n"); return -1; + } } } /* Send a cancellation flag back to the library. */ -void +int cancel_receive (void) { XDR xdr; @@ -385,11 +457,11 @@ cancel_receive (void) if (xwrite (sock, fbuf, sizeof fbuf) == -1) { perror ("write to socket"); - return; + return -1; } /* Keep receiving chunks and discarding, until library sees cancel. */ - (void) receive_file (NULL, NULL); + return receive_file (NULL, NULL); } static int check_for_library_cancellation (void); @@ -403,7 +475,7 @@ send_file_write (const void *buf, int len) int cancel; if (len > GUESTFS_MAX_CHUNK_SIZE) { - fprintf (stderr, "send_file_write: len (%d) > GUESTFS_MAX_CHUNK_SIZE (%d)\n", + fprintf (stderr, "guestfsd: send_file_write: len (%d) > GUESTFS_MAX_CHUNK_SIZE (%d)\n", len, GUESTFS_MAX_CHUNK_SIZE); return -1; } @@ -459,7 +531,7 @@ check_for_library_cancellation (void) xdr_destroy (&xdr); if (flag != GUESTFS_CANCEL_FLAG) { - fprintf (stderr, "check_for_library_cancellation: read 0x%x from library, expected 0x%x\n", + fprintf (stderr, "guestfsd: check_for_library_cancellation: read 0x%x from library, expected 0x%x\n", flag, GUESTFS_CANCEL_FLAG); return 0; } @@ -488,7 +560,7 @@ send_chunk (const guestfs_chunk *chunk) xdrmem_create (&xdr, buf, sizeof buf, XDR_ENCODE); if (!xdr_guestfs_chunk (&xdr, (guestfs_chunk *) chunk)) { - fprintf (stderr, "send_chunk: failed to encode chunk\n"); + fprintf (stderr, "guestfsd: send_chunk: failed to encode chunk\n"); xdr_destroy (&xdr); return -1; } @@ -503,9 +575,198 @@ send_chunk (const guestfs_chunk *chunk) int err = (xwrite (sock, lenbuf, 4) == 0 && xwrite (sock, buf, len) == 0 ? 0 : -1); if (err) { - fprintf (stderr, "send_chunk: write failed\n"); + fprintf (stderr, "guestfsd: send_chunk: write failed\n"); exit (EXIT_FAILURE); } return err; } + +/* Initial delay before sending notification messages, and + * the period at which we send them thereafter. These times + * are in microseconds. + */ +#define NOTIFICATION_INITIAL_DELAY 2000000 +#define NOTIFICATION_PERIOD 333333 + +void +notify_progress (uint64_t position, uint64_t total) +{ + struct timeval now_t; + gettimeofday (&now_t, NULL); + + /* Always send a notification at 100%. This simplifies callers by + * allowing them to 'finish' the progress bar at 100% without + * needing special code. + */ + if (count_progress > 0 && position == total) + goto send; + + /* Calculate time in microseconds since the last progress message + * was sent out (or since the start of the call). + */ + int64_t last_us, now_us, elapsed_us; + last_us = + (int64_t) last_progress_t.tv_sec * 1000000 + last_progress_t.tv_usec; + now_us = (int64_t) now_t.tv_sec * 1000000 + now_t.tv_usec; + elapsed_us = now_us - last_us; + + /* Rate limit. */ + if ((count_progress == 0 && elapsed_us < NOTIFICATION_INITIAL_DELAY) || + (count_progress > 0 && elapsed_us < NOTIFICATION_PERIOD)) + return; + + send: + /* We're going to send a message now ... */ + count_progress++; + last_progress_t = now_t; + + /* Send the header word. */ + XDR xdr; + char buf[128]; + uint32_t i = GUESTFS_PROGRESS_FLAG; + size_t len; + xdrmem_create (&xdr, buf, 4, XDR_ENCODE); + xdr_u_int (&xdr, &i); + xdr_destroy (&xdr); + + if (xwrite (sock, buf, 4) == -1) { + fprintf (stderr, "guestfsd: xwrite failed\n"); + exit (EXIT_FAILURE); + } + + guestfs_progress message = { + .proc = proc_nr, + .serial = serial, + .position = position, + .total = total, + }; + + xdrmem_create (&xdr, buf, sizeof buf, XDR_ENCODE); + if (!xdr_guestfs_progress (&xdr, &message)) { + fprintf (stderr, "guestfsd: xdr_guestfs_progress: failed to encode message\n"); + xdr_destroy (&xdr); + return; + } + len = xdr_getpos (&xdr); + xdr_destroy (&xdr); + + if (xwrite (sock, buf, len) == -1) { + fprintf (stderr, "guestfsd: xwrite failed\n"); + exit (EXIT_FAILURE); + } +} + +/* "Pulse mode" progress messages. */ + +#if defined(HAVE_SETITIMER) && defined(HAVE_SIGACTION) + +static void async_safe_send_pulse (int sig); + +void +pulse_mode_start (void) +{ + struct sigaction act; + struct itimerval it; + + memset (&act, 0, sizeof act); + act.sa_handler = async_safe_send_pulse; + act.sa_flags = SA_RESTART; + + if (sigaction (SIGALRM, &act, NULL) == -1) { + perror ("pulse_mode_start: sigaction"); + return; + } + + it.it_value.tv_sec = NOTIFICATION_INITIAL_DELAY / 1000000; + it.it_value.tv_usec = NOTIFICATION_INITIAL_DELAY % 1000000; + it.it_interval.tv_sec = NOTIFICATION_PERIOD / 1000000; + it.it_interval.tv_usec = NOTIFICATION_PERIOD % 1000000; + + if (setitimer (ITIMER_REAL, &it, NULL) == -1) + perror ("pulse_mode_start: setitimer"); +} + +void +pulse_mode_end (void) +{ + pulse_mode_cancel (); /* Cancel the itimer. */ + + notify_progress (1, 1); +} + +void +pulse_mode_cancel (void) +{ + int err = errno; /* Function must preserve errno. */ + struct itimerval it; + struct sigaction act; + + /* Setting it_value to zero cancels the itimer. */ + it.it_value.tv_sec = 0; + it.it_value.tv_usec = 0; + it.it_interval.tv_sec = 0; + it.it_interval.tv_usec = 0; + + if (setitimer (ITIMER_REAL, &it, NULL) == -1) + perror ("pulse_mode_cancel: setitimer"); + + memset (&act, 0, sizeof act); + act.sa_handler = SIG_DFL; + + if (sigaction (SIGALRM, &act, NULL) == -1) + perror ("pulse_mode_cancel: sigaction"); + + errno = err; +} + +/* Send a position = 0, total = 1 (pulse mode) message. The tricky + * part is we have to do it without invoking any non-async-safe + * functions (see signal(7) for a list). Therefore, KISS. + */ +static void +async_safe_send_pulse (int sig) +{ + /* XDR is a RFC ... */ + unsigned char msg[] = { + (GUESTFS_PROGRESS_FLAG & 0xff000000) >> 24, + (GUESTFS_PROGRESS_FLAG & 0x00ff0000) >> 16, + (GUESTFS_PROGRESS_FLAG & 0x0000ff00) >> 8, + GUESTFS_PROGRESS_FLAG & 0x000000ff, + (proc_nr & 0xff000000) >> 24, + (proc_nr & 0x00ff0000) >> 16, + (proc_nr & 0x0000ff00) >> 8, + proc_nr & 0x000000ff, + (serial & 0xff000000) >> 24, + (serial & 0x00ff0000) >> 16, + (serial & 0x0000ff00) >> 8, + serial & 0x000000ff, + /* 64 bit position = 0 */ 0, 0, 0, 0, 0, 0, 0, 0, + /* 64 bit total = 1 */ 0, 0, 0, 0, 0, 0, 0, 1 + }; + + if (xwrite (sock, msg, sizeof msg) == -1) + exit (EXIT_FAILURE); +} + +#else /* !HAVE_SETITIMER || !HAVE_SIGACTION */ + +void +pulse_mode_start (void) +{ + /* empty */ +} + +void +pulse_mode_end (void) +{ + /* empty */ +} + +void +pulse_mode_cancel (void) +{ + /* empty */ +} + +#endif /* !HAVE_SETITIMER || !HAVE_SIGACTION */