(Thanks to Yufang Zhang for helping to debug this issue). (cherry picked from commit 199f218bf431b77c12a728f7072bed1553a0f0af)
libguestfs-supermin-helper was previously a shell script. Although
we had steadily optimized it, there were a number of intractable
hot spots:
(1) cpio still reads input files in 512 byte chunks; this is *very*
pessimal behaviour, particularly when SELinux is enabled.
(2) the hostfiles globbing was done very inefficiently by the shell,
with the shell rereading the same directory over and over again.
This is a rewrite of this shell script in C. It is approximately
3 times faster without SELinux, and has an even greater speed difference
with SELinux.
The main features are:
(a) It never frees memory, making it simpler. The program is designed
to run and exit in sub-second times, so this is acceptable.
(b) It caches directory reads, making the globbing of host files much
faster (measured this as ~ 4 x speed up).
(c) It doesn't use external cpio, but instead contains code to write
newc format cpio files, which is all that the kernel can read. Unlike
cpio, this code uses large buffers for reads and writes.
(d) Ignores missing or unreadable hostfiles, whereas cpio gave a
warning.
(e) Checks all return values from system calls.
(f) With --verbose flag, it will print messages timing itself.
This passes all tests.
Updated with feedback from Jim Meyering.
Tested in only limited situations, with Mono on Linux.
These manual pages have for a very long time 'lived' in the top source directory. Clean up this situation by moving those manual pages (plus associated generated files) into the src/ and fish/ subdirectories respectively.
This fixes commit cada248a53858341c91f70392e8f5b6e47d9b4fe.
This change adds an explicit dependency on generator.ml for every file it generates, except java files. Java is left for another time because it's considerably trickier. It also adds a build rule for src/libguestfs.la so it can be rebuilt as required from other directories. It does this by creating a top level make file, subdir-rules.mk, which can be included from sub-directories. sub-directories need to define 'generator_built' to include local files which are built by generator.ml, and they will be updated automatically. This fixes parallel make, and will automatically re-create generated files when make is run from any directory. It also fixes the problem which efad4f53 was targetting. Specifically, src/guestfs_protocol.(c|h) had an erroneous dependency on stamp-generator, and therefore generator.ml, despite not being directly created by it. This caused them to be recreated every time generator.ml ran rather than only when src/guestfs_protocol.x was updated, which cascaded into a daemon and therefore appliance update. This patch also changes the contents of the distribution tarball by including files created by rpcgen.