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2015-02-02macro: document that DECIMAL_STR_MAX contains space for the trailing NUL byteLennart Poettering
2015-01-24tmpfiles: do not bump access times of directories we are cleaning upZbigniew Jędrzejewski-Szmek
Both plain opendir() and glob() will bump access time. Privileged option O_NOATIME can be used to prevent the access time from being updated. We already used it for subdirectories of the directories which we were cleaning up. But for the directories specified directly in the config files, we wouldn't do that. This means that, paradoxically, our own temporary directories for PrivateTmp would stay around forever, as long as one let systemd-tmpfiles-clean.service run regularly, because they had their own glob patterns specified. https://bugzilla.redhat.com/show_bug.cgi?id=1183684
2015-01-23build-sys: fix build on compilers without static_assertZbigniew Jędrzejewski-Szmek
Build would fail when assert was used on the same line in different files #included together. https://bugs.freedesktop.org/show_bug.cgi?id=87339
2015-01-18Move DEFINE_TRIVIAL_CLEANUP_FUNC to macro.hZbigniew Jędrzejewski-Szmek
This remove the need for various header files to include the (relatively heavyweight) util.h.
2015-01-09logind: unify how we cast between uid_t and pointers for hashmap keysLennart Poettering
2014-12-30macro: add DIV_ROUND_UP()David Herrmann
This macro calculates A / B but rounds up instead of down. We explicitly do *NOT* use: (A + B - 1) / A as it suffers from an integer overflow, even though the passed values are properly tested against overflow. Our test-cases show this behavior. Instead, we use: A / B + !!(A % B) Note that on "Real CPUs" this does *NOT* result in two divisions. Instead, instructions like idivl@x86 provide both, the quotient and the remainder. Therefore, both algorithms should perform equally well (I didn't verify this, though).
2014-12-08sd-bus: rework ELF error mapping table magicLennart Poettering
The ELF magic cannot work for consumers of our shard library, since they are in a different module. Hence make all the ELF magic private, and instead introduce a public function to register additional static mapping table.
2014-11-28treewide: introduce UID_INVALID (and friends) as macro for (uid_t) -1Lennart Poettering
2014-11-26Introduce CONF_DIRS_NULSTR helper to define standard conf dirsJosh Triplett
Several different systemd tools define a nulstr containing a standard series of configuration file directories, in /etc, /run, /usr/local/lib, /usr/lib, and (#ifdef HAVE_SPLIT_USR) /lib. Factor that logic out into a new helper macro, CONF_DIRS_NULSTR.
2014-08-28macro: use unique variable names for math-macrosDavid Herrmann
Similar to container_of(), we now use unique variable names for the bascic math macros MAX, MIN, CLAMP, LESS_BY. Furthermore, unit tests are added to verify they work as expected. For a rationale, see: commit fb835651aff79a1e7fc5795086c9b26e59a8e6ca Author: David Herrmann <dh.herrmann@gmail.com> Date: Fri Aug 22 14:41:37 2014 +0200 shared: make container_of() use unique variable names
2014-08-27shared: make container_of() use unique variable namesDavid Herrmann
If you stack container_of() macros, you will get warnings due to shadowing variables of the parent context. To avoid this, use unique names for variables. Two new helpers are added: UNIQ: This evaluates to a truly unique value never returned by any evaluation of this macro. It's a shortcut for __COUNTER__. UNIQ_T: Takes two arguments and concatenates them. It is a shortcut for CONCATENATE, but meant to defined typed local variables. As you usually want to use variables that you just defined, you need to reference the same unique value at least two times. However, UNIQ returns a new value on each evaluation, therefore, you have to pass the unique values into the macro like this: #define my_macro(a, b) __max_macro(UNIQ, UNIQ, (a), (b)) #define __my_macro(uniqa, uniqb, a, b) ({ typeof(a) UNIQ_T(A, uniqa) = (a); typeof(b) UNIQ_T(B, uniqb) = (b); MY_UNSAFE_MACRO(UNIQ_T(A, uniqa), UNIQ_T(B, uniqb)); }) This way, MY_UNSAFE_MACRO() can safely evaluate it's arguments multiple times as they are local variables. But you can also stack invocations to the macro my_macro() without clashing names. This is the same as if you did: #define my_macro(a, b) __max_macro(__COUNTER__, __COUNTER__, (a), (b)) #define __my_macro(prefixa, prefixb, a, b) ({ typeof(a) CONCATENATE(A, prefixa) = (a); typeof(b) CONCATENATE(B, prefixb) = (b); MY_UNSAFE_MACRO(CONCATENATE(A, prefixa), CONCATENATE(B, prefixb)); }) ...but in my opinion, the first macro is easier to write and read. This patch starts by converting container_of() to use this new helper. Other macros may follow (like MIN, MAX, CLAMP, ...).
2014-08-27shared: drop UNIQUE()David Herrmann
The UNIQUE() macro works fine if used in un-stacked macros. However, once you stack them like: MAX(MIN(a, b), CLAMP(MAX(c, d), e, f)) you will get warnings due to shadowing other variables. gcc uses the last line of a macro expansion as value for __LINE__, therefore, we cannot even avoid this by splitting the expressions across lines. Remove the only user of UNIQUE() so we introduce a new helper in follow-ups.
2014-08-22shared: add MAXSIZE() and use it in resolvedDavid Herrmann
The MAXSIZE() macro takes two types and returns the size of the larger one. It is much simpler to use than MAX(sizeof(A), sizeof(B)) and also avoids any compiler-extensions, unlike CONST_MAX() and MAX() (which are needed to avoid evaluating arguments more than once). This was suggested by Daniele Nicolodi <daniele@grinta.net>. Also make resolved use this macro instead of CONST_MAX(). This enhances readability quite a bit.
2014-08-15macro: add CONST_MAX() macroDavid Herrmann
The CONST_MAX() macro is similar to MAX(), but verifies that both arguments have the same type and are constant expressions. Furthermore, the result of CONST_MAX() is again a constant-expression. CONST_MAX() avoids any statement-expressions and other non-trivial expression-types. This avoids rather arbitrary restrictions in both GCC and LLVM, which both either fail with statement-expressions inside type-declarations or statement-expressions inside static-const initializations. If anybody knows how to circumvent this, please feel free to unify CONST_MAX() and MAX().
2014-08-15macro: const'ify MIN/MAX/... macrosDavid Herrmann
We must add 'const' to local variables in statement-expressions to guarantee that the macros can produce constant-expressions if given such. GCC seems to ignore this, but LLVM/clang requires it (understandably).
2014-07-16resolved: add a DNS client stub resolverLennart Poettering
Let's turn resolved into a something truly useful: a fully asynchronous DNS stub resolver that subscribes to network changes. (More to come: caching, LLMNR, mDNS/DNS-SD, DNSSEC, IDN, NSS module)
2014-07-11shared: add MIN3 macroDavid Herrmann
This is like MIN but evaluates 3 arguments. We already have MAX3, so add the equivalent for MIN.
2014-06-16macro: add DISABLE_WARNING_SHADOWDavid Herrmann
As it turns out, we cannot use _Pragma in compound-statements. Therefore, constructs like MIN(MAX(a, b), x) will warn due to shadowed variable declarations. The DISABLE_WARNING_SHADOW macro can be used to suppress these. Note that using UNIQUE(_var) does not work either as GCC uses the last line of a macro-expansion for __LINE__, therefore, still causing both macros to have the same variables. We could use different variable-names for MIN and MAX, but that just hides the problem and still fails for MIN(something(MIN(a, b)), c). The only working solution is to use __COUNTER__ and pass it pre-evaluated as extra argument to a macro to use as name-prefix. This, however, makes all these macros much more complicated so I'll go with manual DISABLE_WARNING_SHADOW so far.
2014-05-13shared: add ALIGN_POWER2 macroDavid Herrmann
Sounds easy, turns out to be horrible to implement: ALIGN_POWER2 returns the next higher power of 2. clz(0) is undefined, same is true for left-shift-overflows, yey, C rocks!
2014-03-12macro: make sure we can use IN_SET() also with complex function calls as ↵Lennart Poettering
first argument
2014-03-04logind: make $XDG_RUNTIME_DIR a per-user tmpfsLennart Poettering
This way each user allocates from his own pool, with its own size limit. This puts the size limit by default to 10% of the physical RAM size but makes it configurable in logind.conf.
2014-02-20macro: add nice macro for disabling -Wnonnull temporarilyLennart Poettering
2014-02-20macro: introduce nice macro for disabling -Wmissing-prototypes warnigsLennart Poettering
2014-02-20macro: introduce a nice macro for disabling -Wformat-nonliteral temporarilyLennart Poettering
2014-02-20util: get rid of warnings around assert_cc() macroLennart Poettering
Suggested by Holger Schurig.
2014-01-11journald: do not free space when disk space runs lowZbigniew Jędrzejewski-Szmek
Before, journald would remove journal files until both MaxUse= and KeepFree= settings would be satisfied. The first one depends (if set automatically) on the size of the file system and is constant. But the second one depends on current use of the file system, and a spike in disk usage would cause journald to delete journal files, trying to reach usage which would leave 15% of the disk free. This behaviour is surprising for the user who doesn't expect his logs to be purged when disk usage goes above 85%, which on a large disk could be some gigabytes from being full. In addition attempting to keep 15% free provides an attack vector where filling the disk sufficiently disposes of almost all logs. Instead, obey KeepFree= only as a limit on adding additional files. When replacing old files with new, ignore KeepFree=. This means that if journal disk usage reached some high point that at some later point start to violate the KeepFree= constraint, journald will not add files to go above this point, but it will stay (slightly) below it. When journald is restarted, it forgets the previous maximum usage value, and sets the limit based on the current usage, so if disk remains to be filled, journald might use one journal-file-size less on each restart, if restarts happen just after rotation. This seems like a reasonable compromise between implementation complexity and robustness.
2013-12-17_noreturn_ --> noreturn for C11 compatShawn Landden
also define noreturn w/o <stdnoreturn.h>
2013-12-17__thread --> thread_local for C11 compatShawn Landden
Also make thread_local available w/o including <threads.h>. (as the latter hasn't been implemented, but this part is trivial)
2013-12-10macro: log assertion at debug level in assert_return()Lennart Poettering
2013-12-03macro: better make IN_SET() macro use const arraysLennart Poettering
2013-12-02macro: add a macro to test whether a value is in a specified listLennart Poettering
Introduce IN_SET() macro to nicely check whether a value a is one of a few listed values. This makes writing this: if (a == 1 || a == 7 || a == 8 || a == 9) nicer, by allowing this: if (IN_SET(a, 1, 7, 8, 9)) This is particularly useful for state machine enums.
2013-11-30macro.h: fix typo in commentThomas Hindoe Paaboel Andersen
2013-11-25swap: split state machine state ACTIVATING into twoLennart Poettering
We expect the event on /proc/swaps before we expect the SIGCHILD, reflect this in the state machine.
2013-11-22macro: fix problem with __LINE__ macro expansionLukasz Skalski
David: I already applied a fix for that, but this patch definitely looks nicer. I changed CONCATENATE_HELPER() -> XCONCATENATE() similar to XSTRINGIFY and added the UNIQUE() helper.
2013-11-22macro: fix assert_cc() fallbackDavid Herrmann
We need two-level macro-expansion, otherwise __LINE__ will not get evaluated.
2013-11-20macro: add _unlikely_() to assert_return()Lennart Poettering
As the name indicates assert_return() is really just for assertions, i.e. where it's a programming error if the assertion does not hold. Hence it is safe to add _unlikely_() decorators for the expression to check.
2013-11-20macro: change assert_cc() so that it can appear outside of functionsLennart Poettering
2013-11-07util: add circle to special chars we can drawLennart Poettering
2013-10-21bus: remove static introspection file exportKay Sievers
2013-10-16macro: clean up usage of gcc attributesLennart Poettering
Always use our own macros, and name all our own macros the same style.
2013-10-11macro: add new assert_return() macro for early parameter checking in functionsLennart Poettering
For the library functions we expose we currently repeatedly use checks like the following: if (!value_is_ok(parameter1)) return -EINVAL; if (!value_is_ok(parameter2)) return -EINVAL; And so on. Let's turn this into a macro: assert_return(value_is_ok(parameter1), -EINVAL); assert_return(value_is_ok(paramater2), -EINVAL); This makes our code a bit shorter and simpler, and also allows us to add a _unlikely_() around the check.
2013-08-22remove hasprefix(), use startswith()Shawn Landden
2013-08-20Rename F_TYPE_CMP() to F_TYPE_EQUAL()Zbigniew Jędrzejewski-Szmek
2013-06-20Add hasprefix macro to check prefixes of fixed lengthZbigniew Jędrzejewski-Szmek
2013-05-17bus: add APIs for negotiating what is attached to messagesLennart Poettering
2013-05-14bus: add and use UINT64_TO_PTR()Kay Sievers
2013-04-25Make up for attribute malloc with alloc_sizeZbigniew Jędrzejewski-Szmek
It is imperative that open source code be well attributed. Sprinkle attribute((alloc_size)) here and there, telling gcc how much memory we are actually allocating.
2013-04-19Reintroduce f_type comparison macroHarald Hoyer
This reverts commit 4826f0b7b5c0aefa08b8cc7ef64d69027f84da2c. Because statfs.t_type can be int on some architecures, we have to cast the const magic to the type, otherwise the compiler warns about signed/unsigned comparison, because the magic can be 32 bit unsigned. statfs(2) man page is also wrong on some systems, because f_type is not __SWORD_TYPE on some architecures. The following program: int main(int argc, char**argv) { struct statfs s; statfs(argv[1], &s); printf("sizeof(f_type) = %d\n", sizeof(s.f_type)); printf("sizeof(__SWORD_TYPE) = %d\n", sizeof(__SWORD_TYPE)); printf("sizeof(long) = %d\n", sizeof(long)); printf("sizeof(int) = %d\n", sizeof(int)); if (sizeof(s.f_type) == sizeof(int)) { printf("f_type = 0x%x\n", s.f_type); } else { printf("f_type = 0x%lx\n", s.f_type); } return 0; } executed on s390x gives for a btrfs: sizeof(f_type) = 4 sizeof(__SWORD_TYPE) = 8 sizeof(long) = 8 sizeof(int) = 4 f_type = 0x9123683e
2013-04-18Revert f_type fixupsHarald Hoyer
This reverts commit a858b64dddf79177e12ed30f5e8c47a1471c8bfe. This reverts commit aea275c43194b6ac519ef907b62c5c995050fde0. This reverts commit fc6e6d245ee3989c222a2a8cc82a33475f9922f3. This reverts commit c4073a27c555aeceac87a3b02a83141cde641a1e. This reverts commit cddf148028f525be8176e7f1cbbf4f862bd287f6. This reverts commit 8c68a70170b31f93c287f29fd06c6c17edaf19ad. The constants are now casted to __SWORD_TYPE, which should resolve the compiler warnings about signed vs unsigned. After talking to Kay, we concluded: This should be fixed in the kernel, not worked around in userspace tools. Architectures cannot use int and expect magic constants lager than INT_MAX to work correctly. The kernel header needs to be fixed. Even coreutils cannot handle it: #define RAMFS_MAGIC 0x858458f6 # stat -f -c%t / ffffffff858458f6 #define BTRFS_SUPER_MAGIC 0x9123683E # stat -f -c%t /mnt ffffffff9123683e Although I found the perfect working macro to fix the thing :) __extension__ ({ \ bool _ret = false; \ switch(f) { case c: _ret=true; }; \ ( _ret ); \ })
2013-04-18macro.h: let F_TYPE_CMP() macro fail to compile, if second parameter is not ↵Harald Hoyer
const If the magic parameter is not a const, then the macro does not work, so better fail to compile, than be surprised afterwards.