diff options
author | Jérôme Pouiller <jezz@sysmic.org> | 2016-12-20 14:46:18 +0100 |
---|---|---|
committer | Peter Korsgaard <peter@korsgaard.com> | 2017-02-07 21:45:01 +0100 |
commit | 76838f63412a30a358210e457dda4b79f7730624 (patch) | |
tree | 5aedfd22c554ac89916fcd73c62186c74afe9eb9 /toolchain | |
parent | d3760efa7b92da74c39f5673c591b4fa14886b76 (diff) |
reproducible: fix DATE/TIME macros in toolchain-wrapper
The use of the __DATE__ and __TIME__ macros are one of the most common
sources of non-reproducible binaries. In order to fix that, gcc 7 supports
the SOURCE_DATE_EPOCH variable:
https://gcc.gnu.org/git/?p=gcc.git;a=commitdiff;h=e3e8c48c4a494d9da741c1c8ea6c4c0b7c4ff934
This patch take advantage of toolchain-wrapper to provide support of
SOURCE_DATE_EPOCH to older gcc versions.
Function get_source_date_epoch() come directly from gcc git.
This work was sponsored by `BA Robotic Systems'.
[Peter: use sizeof for character array sizes, make function static,
extend commit message, add upstream gcc commit]
Signed-off-by: Jérôme Pouiller <jezz@sysmic.org>
Reviewed-by: Samuel Martin <s.martin49@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Diffstat (limited to 'toolchain')
-rw-r--r-- | toolchain/toolchain-wrapper.c | 72 |
1 files changed, 71 insertions, 1 deletions
diff --git a/toolchain/toolchain-wrapper.c b/toolchain/toolchain-wrapper.c index 100aa181c..eb4ee8de4 100644 --- a/toolchain/toolchain-wrapper.c +++ b/toolchain/toolchain-wrapper.c @@ -22,12 +22,15 @@ #include <unistd.h> #include <stdlib.h> #include <errno.h> +#include <time.h> #ifdef BR_CCACHE static char ccache_path[PATH_MAX]; #endif static char path[PATH_MAX]; static char sysroot[PATH_MAX]; +static char source_time[sizeof("-D__TIME__=\"HH:MM:SS\"")]; +static char source_date[sizeof("-D__DATE__=\"MMM DD YYYY\"")]; /** * GCC errors out with certain combinations of arguments (examples are @@ -39,8 +42,11 @@ static char sysroot[PATH_MAX]; * -mfloat-abi= * -march= * -mcpu= + * -D__TIME__= + * -D__DATE__= + * -Wno-builtin-macro-redefined */ -#define EXCLUSIVE_ARGS 3 +#define EXCLUSIVE_ARGS 6 static char *predef_args[] = { #ifdef BR_CCACHE @@ -157,6 +163,47 @@ static void check_unsafe_path(const char *arg, } } +/* Read SOURCE_DATE_EPOCH from environment to have a deterministic + * timestamp to replace embedded current dates to get reproducible + * results. Returns -1 if SOURCE_DATE_EPOCH is not defined. + */ +static time_t get_source_date_epoch() +{ + char *source_date_epoch; + long long epoch; + char *endptr; + + source_date_epoch = getenv("SOURCE_DATE_EPOCH"); + if (!source_date_epoch) + return (time_t) -1; + + errno = 0; + epoch = strtoll(source_date_epoch, &endptr, 10); + if ((errno == ERANGE && (epoch == LLONG_MAX || epoch == LLONG_MIN)) + || (errno != 0 && epoch == 0)) { + fprintf(stderr, "environment variable $SOURCE_DATE_EPOCH: " + "strtoll: %s\n", strerror(errno)); + exit(2); + } + if (endptr == source_date_epoch) { + fprintf(stderr, "environment variable $SOURCE_DATE_EPOCH: " + "no digits were found: %s\n", endptr); + exit(2); + } + if (*endptr != '\0') { + fprintf(stderr, "environment variable $SOURCE_DATE_EPOCH: " + "trailing garbage: %s\n", endptr); + exit(2); + } + if (epoch < 0) { + fprintf(stderr, "environment variable $SOURCE_DATE_EPOCH: " + "value must be nonnegative: %lld \n", epoch); + exit(2); + } + + return (time_t) epoch; +} + int main(int argc, char **argv) { char **args, **cur, **exec_args; @@ -167,6 +214,7 @@ int main(int argc, char **argv) char *paranoid_wrapper; int paranoid; int ret, i, count = 0, debug; + time_t source_date_epoch; /* Calculate the relative paths */ basename = strrchr(progpath, '/'); @@ -272,6 +320,28 @@ int main(int argc, char **argv) } #endif /* ARCH || CPU */ + source_date_epoch = get_source_date_epoch(); + if (source_date_epoch != -1) { + struct tm *tm = localtime(&source_date_epoch); + if (!tm) { + perror("__FILE__: localtime"); + return 3; + } + ret = strftime(source_time, sizeof(source_time), "-D__TIME__=\"%T\"", tm); + if (!ret) { + perror("__FILE__: overflow"); + return 3; + } + *cur++ = source_time; + ret = strftime(source_date, sizeof(source_date), "-D__DATE__=\"%b %e %Y\"", tm); + if (!ret) { + perror("__FILE__: overflow"); + return 3; + } + *cur++ = source_date; + *cur++ = "-Wno-builtin-macro-redefined"; + } + paranoid_wrapper = getenv("BR_COMPILER_PARANOID_UNSAFE_PATH"); if (paranoid_wrapper && strlen(paranoid_wrapper) > 0) paranoid = 1; |