We already set fetchTimeout to 10 seconds, but this does not apply for some of the connection setup steps such as connect(). This left us hanging in a few places where we would normally be stuck in a system call for an indeterminate amount of time.
This addresses FS#15369, which has grown to include and duplicate several other bugs and failures such as specifying a non-existent FTP server, DSL disconnections, etc. Signed-off-by: Dan McGee <[email protected]> --- Anyone that wants to look this over, it was pretty simple and kills one of our long-lingering issues before a 3.5.0 release. The output isn't necessarily beautiful, but it at least doesn't hang forever now. I tested this by adding a line like Server = ftp://192.168.4.4/$repo/os/$arch to my /etc/pacman.d/mirrorlist file, and then running pacman -Sy. $ sudo ./src/pacman/pacman -Sy Password: :: Synchronizing package databases... testing is up to date error: failed retrieving file 'core.db' from 192.168.4.4 : Interrupted system call core is up to date error: failed retrieving file 'extra.db' from 192.168.4.4 : Interrupted system call extra is up to date community-testing is up to date error: failed retrieving file 'multilib.db' from 192.168.4.4 : Interrupted system call multilib is up to date error: failed retrieving file 'community.db' from 192.168.4.4 : Interrupted system call community is up to date -Dan lib/libalpm/dload.c | 21 +++++++++++++++++---- 1 files changed, 17 insertions(+), 4 deletions(-) diff --git a/lib/libalpm/dload.c b/lib/libalpm/dload.c index 7a98eb1..44ff17c 100644 --- a/lib/libalpm/dload.c +++ b/lib/libalpm/dload.c @@ -88,10 +88,10 @@ static const char *gethost(struct url *fileurl) int dload_interrupted; static void inthandler(int signum) { - dload_interrupted = 1; + dload_interrupted = signum; } -#define check_stop() if(dload_interrupted) { ret = -1; goto cleanup; } +#define check_stop() do { alarm(0); if(dload_interrupted) { ret = -1; goto cleanup; } } while(0) enum sighandlers { OLD = 0, NEW = 1 }; static int download_internal(const char *url, const char *localpath, @@ -102,7 +102,7 @@ static int download_internal(const char *url, const char *localpath, off_t dl_thisfile = 0; ssize_t nread = 0; char *tempfile, *destfile, *filename; - struct sigaction sig_pipe[2], sig_int[2]; + struct sigaction sig_pipe[2], sig_int[2], sig_alrm[2]; off_t local_size = 0; time_t local_time = 0; @@ -169,6 +169,12 @@ static int download_internal(const char *url, const char *localpath, sigaction(SIGINT, NULL, &sig_int[OLD]); sigaction(SIGINT, &sig_int[NEW], NULL); + sig_alrm[NEW].sa_handler = &inthandler; + sigemptyset(&sig_alrm[NEW].sa_mask); + sig_alrm[NEW].sa_flags = 0; + sigaction(SIGALRM, NULL, &sig_alrm[OLD]); + sigaction(SIGALRM, &sig_alrm[NEW], NULL); + /* NOTE: libfetch does not reset the error code, be sure to do it before * calls into the library */ @@ -184,7 +190,9 @@ static int download_internal(const char *url, const char *localpath, * trouble in trying to do both size and "if-modified-since" logic in a * non-stat request, so avoid it. */ fetchLastErrCode = 0; + alarm(fetchTimeout); if(fetchStat(fileurl, &ust, "") == -1) { + alarm(0); pm_errno = PM_ERR_LIBFETCH; _alpm_log(PM_LOG_ERROR, _("failed retrieving file '%s' from %s : %s\n"), filename, gethost(fileurl), fetchLastErrString); @@ -211,6 +219,7 @@ static int download_internal(const char *url, const char *localpath, } fetchLastErrCode = 0; + alarm(fetchTimeout); dlf = fetchGet(fileurl, ""); check_stop(); @@ -252,6 +261,7 @@ static int download_internal(const char *url, const char *localpath, handle->dlcb(filename, 0, ust.size); } + alarm(fetchTimeout); while((nread = fetchIO_read(dlf, buffer, PM_DLBUF_LEN)) > 0) { check_stop(); size_t nwritten = 0; @@ -268,7 +278,9 @@ static int download_internal(const char *url, const char *localpath, if(handle->dlcb) { handle->dlcb(filename, dl_thisfile, ust.size); } + alarm(fetchTimeout); } + alarm(0); /* did the transfer complete normally? */ if (nread == -1) { @@ -333,10 +345,11 @@ cleanup: fetchFreeURL(fileurl); /* restore the old signal handlers */ + sigaction(SIGALRM, &sig_alrm[OLD], NULL); sigaction(SIGINT, &sig_int[OLD], NULL); sigaction(SIGPIPE, &sig_pipe[OLD], NULL); /* if we were interrupted, trip the old handler */ - if(dload_interrupted) { + if(dload_interrupted == SIGINT) { raise(SIGINT); } -- 1.7.4
