Fixes FS#18770, and hopefully an occasional deadlock in my frontend as well. For simplicity it redirects all scriptlet output through SCRIPTLET_INFO, and all callbacks in the child process have been replaced for thread-safety. Also adds a shell to the fake root set up for pactests, which was not needed previously due to a bug (debian #582847) in fakechroot. Signed-off-by: Jonathan Conder --- lib/libalpm/util.c | 91 +++++++++++++++++++++++++++++------------------- test/pacman/pmtest.py | 5 ++- 2 files changed, 59 insertions(+), 37 deletions(-) I noticed the list has been quiet for a while, so I thought this would be a good time to resubmit. Only change here is the location of the pactest, which git moved automagically :). I am nearly certain now that this will fix the deadlock in my frontend (for details see the RATIONALE section of man pthread_atfork). diff --git a/lib/libalpm/util.c b/lib/libalpm/util.c index ffebe9e..46460f0 100644 --- a/lib/libalpm/util.c +++ b/lib/libalpm/util.c @@ -456,6 +456,7 @@ int _alpm_run_chroot(const char *root, const char *cmd) { char cwd[PATH_MAX]; pid_t pid; + int pipefd[2]; int restore_cwd = 0; int retval = 0; @@ -479,6 +480,12 @@ int _alpm_run_chroot(const char *root, const char *cmd) /* Flush open fds before fork() to avoid cloning buffers */ fflush(NULL); + if(pipe(pipefd) == -1) { + _alpm_log(PM_LOG_ERROR, _("could not create pipe (%s)\n"), strerror(errno)); + retval = 1; + goto cleanup; + } + /* fork- parent and child each have seperate code blocks below */ pid = fork(); if(pid == -1) { @@ -488,55 +495,67 @@ int _alpm_run_chroot(const char *root, const char *cmd) } if(pid == 0) { - FILE *pipe; /* this code runs for the child only (the actual chroot/exec) */ - _alpm_log(PM_LOG_DEBUG, "chrooting in %s\n", root); + close(1); + close(2); + while(dup2(pipefd[1], 1) == -1 && errno == EINTR); + while(dup2(pipefd[1], 2) == -1 && errno == EINTR); + close(pipefd[0]); + close(pipefd[1]); + + /* use fprintf instead of _alpm_log to send output through the parent */ if(chroot(root) != 0) { - _alpm_log(PM_LOG_ERROR, _("could not change the root directory (%s)\n"), - strerror(errno)); + fprintf(stderr, _("could not change the root directory (%s)\n"), strerror(errno)); exit(1); } if(chdir("/") != 0) { - _alpm_log(PM_LOG_ERROR, _("could not change directory to / (%s)\n"), - strerror(errno)); + fprintf(stderr, _("could not change directory to / (%s)\n"), strerror(errno)); exit(1); } umask(0022); - pipe = popen(cmd, "r"); - if(!pipe) { - _alpm_log(PM_LOG_ERROR, _("call to popen failed (%s)\n"), - strerror(errno)); - exit(1); - } - while(!feof(pipe)) { - char line[PATH_MAX]; - if(fgets(line, PATH_MAX, pipe) == NULL) - break; - alpm_logaction("%s", line); - EVENT(handle->trans, PM_TRANS_EVT_SCRIPTLET_INFO, line, NULL); - } - retval = pclose(pipe); - exit(WEXITSTATUS(retval)); + execl("/bin/sh", "sh", "-c", cmd, (char *) NULL); + fprintf(stderr, _("call to execl failed (%s)\n"), strerror(errno)); + exit(1); } else { /* this code runs for the parent only (wait on the child) */ - pid_t retpid; int status; - do { - retpid = waitpid(pid, &status, 0); - } while(retpid == -1 && errno == EINTR); - if(retpid == -1) { - _alpm_log(PM_LOG_ERROR, _("call to waitpid failed (%s)\n"), - strerror(errno)); + FILE *pipe; + + close(pipefd[1]); + pipe = fdopen(pipefd[0], "r"); + if(pipe == NULL) { + close(pipefd[0]); retval = 1; - goto cleanup; } else { - /* check the return status, make sure it is 0 (success) */ - if(WIFEXITED(status)) { - _alpm_log(PM_LOG_DEBUG, "call to waitpid succeeded\n"); - if(WEXITSTATUS(status) != 0) { - _alpm_log(PM_LOG_ERROR, _("command failed to execute correctly\n")); - retval = 1; - } + while(!feof(pipe)) { + char line[PATH_MAX]; + if(fgets(line, PATH_MAX, pipe) == NULL) + break; + alpm_logaction("%s", line); + EVENT(handle->trans, PM_TRANS_EVT_SCRIPTLET_INFO, line, NULL); + } + fclose(pipe); + } + + while(waitpid(pid, &status, 0) == -1) { + if(errno != EINTR) { + _alpm_log(PM_LOG_ERROR, _("call to waitpid failed (%s)\n"), strerror(errno)); + retval = 1; + goto cleanup; + } + } + + /* report error from above after the child has exited */ + if(retval != 0) { + _alpm_log(PM_LOG_ERROR, _("could not open pipe (%s)\n"), strerror(errno)); + goto cleanup; + } + /* check the return status, make sure it is 0 (success) */ + if(WIFEXITED(status)) { + _alpm_log(PM_LOG_DEBUG, "call to waitpid succeeded\n"); + if(WEXITSTATUS(status) != 0) { + _alpm_log(PM_LOG_ERROR, _("command failed to execute correctly\n")); + retval = 1; } } } diff --git a/test/pacman/pmtest.py b/test/pacman/pmtest.py index b1d778e..5c8881c 100755 --- a/test/pacman/pmtest.py +++ b/test/pacman/pmtest.py @@ -110,10 +110,13 @@ def generate(self): tmpdir = os.path.join(self.root, TMPDIR) logdir = os.path.join(self.root, os.path.dirname(LOGFILE)) etcdir = os.path.join(self.root, os.path.dirname(PACCONF)) - for dir in [dbdir, cachedir, syncdir, tmpdir, logdir, etcdir]: + bindir = os.path.join(self.root, "bin") + for dir in [dbdir, cachedir, syncdir, tmpdir, logdir, etcdir, bindir]: if not os.path.isdir(dir): vprint("\t%s" % dir[len(self.root)+1:]) os.makedirs(dir, 0755) + # Only the dynamically linked binary is needed for fakechroot + shutil.copy("/bin/sh", bindir) # Configuration file vprint(" Creating configuration file") -- 1.7.2.1