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Hi, this patch series fixes few more issues discovered by Coverity. Thanks, Pino Toscano (6): tail: check the return value pf guestfs_set_pgroup daemon: btrfs: check end_stringsbuf return values everywhere java: use cleanup handlers for structs (lists) as return values lib: qemu: improve handling of FILE* p2v: check more return values p2v: fix possible close(-1) issue cat/tail.c

...ble. + * + * This caches the results in the cachedir so that as long as the qemu + * binary does not change, calling this is effectively free. */ struct qemu_data * guestfs_int_test_qemu (guestfs_h *g) { + struct qemu_data *data; + struct stat statbuf; + CLEANUP_FREE char *cachedir = NULL, *qemu_stat_filename = NULL, + *qemu_help_filename = NULL, *qemu_devices_filename = NULL; + FILE *fp; + int generation; + uint64_t prev_size, prev_mtime; + + if (stat (g->hv, &statbuf) == -1) { + perrorf (g, "stat: %s", g->hv); + return NULL; + } + + cachedir = guestfs_int_lazy_make_...

...es not change, calling this is effectively free. @@ -73,12 +110,12 @@ static void read_all (guestfs_h *g, void *retv, const char *buf, size_t len); struct qemu_data * guestfs_int_test_qemu (guestfs_h *g) { - struct qemu_data *data; struct stat statbuf; - CLEANUP_FREE char *cachedir = NULL, *qemu_stat_filename = NULL, - *qemu_help_filename = NULL, *qemu_devices_filename = NULL; - int generation; - uint64_t prev_size, prev_mtime; + struct qemu_data *data; + CLEANUP_FREE char *cachedir = NULL; + CLEANUP_FREE char *stat_filename = NULL; + int r; + size_t i; if (stat (g->hv, &statbuf)...

Patches 1 & 2 were posted previously here: https://www.redhat.com/archives/libguestfs/2016-May/msg00134.html Patch 3 is a hack so I can test this using my own version of qemu (the `-L ?' stuff is not upstream). Patch 4 is where the real action takes place: Replace the caching of qemu features in blob-like files with a sqlite database. Probably the best way to approach this patch is to

NOTE: Not for upstream, yet. This depends on 3 non-upstream patches. - The qemu rework in libguestfs, which in turn depends on what Pino is up to. - Support for '-L ?' in qemu: https://lists.gnu.org/archive/html/qemu-devel/2016-05/threads.html#02596 - Support for bios-fast.bin in qemu: https://lists.gnu.org/archive/html/qemu-devel/2016-05/threads.html#02408 This commit

This commit uses -bios bios-fast.bin if available, which basically stops SeaBIOS from trying to do PCI probing during boot, which is a waste of time when using the -kernel option. v1 -> v2: - Rebase on top of Pino's work. This still has 3 dependencies: - The qemu memoization work (v2). - Support for '-L ?' in qemu:

The patch I posted last week to disable mandatory locking for readonly drives (https://www.redhat.com/archives/libguestfs/2017-September/msg00013.html) was wrong in a couple of respects. Firstly it didn't work, which I didn't detect because my tests were testing the wrong thing. Oops. Secondly it used a simple version number check to detect qemu binaries implementing mandatory locking.

v2 -> v3: - I addressed everything that Pino mentioned last time. - It's tricky to get a stable run when multiple copies of qemu are involved, because the same cache files get overwritten by parallel libguestfs. So I changed the names of the cache files to include the qemu binary key (size, mtime), which removes this conflict. This is in new patch 4/6. Rich.

Patches 1-4 are almost the same as they are when previously posted here: https://www.redhat.com/archives/libguestfs/2017-September/msg00039.html Patch 5 actually uses the mandatory locking test to turn off locking in the narrow case where a drive is opened readonly, and then only for the drive being inspected. Passes ordinary tests (‘check-direct’ and ‘check-valgrind-direct’). Rich.

Doing qemu feature detection in the direct backend takes ~100ms because we need to run `qemu -help' and `qemu -devices ?', and each of those interacts with glibc's very slow link loader. Fixing the link loader is really hard. Instead memoize the output of those two commands. This patch series first separates all the code dealing with qemu into a separate module (src/qemu.c) and

v1 -> v2: - Rebase on top of Pino's version work. Two patches went upstream, these are the two remaining patches. Note the generation number is still inside the qemu.stat file. We could put it in the filename, I have no particular preference. Rich.