From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Pouiller?= Date: Wed, 23 Nov 2016 12:08:02 +0100 Subject: [Buildroot] [PATCH v3 02/18] reproducible: fix DATE/TIME macros in toolchain-wrapper In-Reply-To: <1479899298-14655-1-git-send-email-jezz@sysmic.org> References: <1479899298-14655-1-git-send-email-jezz@sysmic.org> Message-ID: <1479899298-14655-3-git-send-email-jezz@sysmic.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net The use __DATE__ and __TIME__ are one of most common sources of non-reproducible binaries. In order to fix that, gcc begin to support SOURCE_DATE_EPOCH variable. 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'. Signed-off-by: J?r?me Pouiller --- toolchain/toolchain-wrapper.c | 74 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 73 insertions(+), 1 deletion(-) diff --git a/toolchain/toolchain-wrapper.c b/toolchain/toolchain-wrapper.c index 925d013..26d01b6 100644 --- a/toolchain/toolchain-wrapper.c +++ b/toolchain/toolchain-wrapper.c @@ -22,12 +22,17 @@ #include #include #include +#include #ifdef BR_CCACHE static char ccache_path[PATH_MAX]; #endif static char path[PATH_MAX]; static char sysroot[PATH_MAX]; +// strlen("-D__TIME__=\"HH:MM:SS\"") + 1 = 22 +static char source_time[22]; +// strlen("-D__DATE__=\"MMM DD YYYY\"") + 1 = 25 +static char source_date[25]; /** * GCC errors out with certain combinations of arguments (examples are @@ -39,8 +44,11 @@ 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 @@ -136,6 +144,47 @@ 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. + */ +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; @@ -146,6 +195,7 @@ 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, '/'); @@ -251,6 +301,28 @@ 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; -- 1.9.1