From: Simon Kuenzer <simon@unikraft.io>
Date: Tue, 10 Oct 2023 11:37:56 +0000 (+0200)
Subject: lib/uklibid: Option to store "Compile date" to `.uklibid_info`
X-Git-Tag: RELEASE-0.15.0~73
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=ea050dbfea219e707dc49d6d225bd8d771291e15;p=unikraft%2Funikraft.git

lib/uklibid: Option to store "Compile date" to `.uklibid_info`

Adds the option to store the compile time and date for a library and
unikernel. When enabled, `libinfo.S` is recompiled on every rebuild. This
is achieved by handing over the current time and date as compile flag.
For this purpose, the build system provides `$(HOSTUTC)`, the current
time and date in UTC format.

Signed-off-by: Simon Kuenzer <simon@unikraft.io>
Reviewed-by: Michalis Pappas <michalis@unikraft.io>
Reviewed-by: Robert Kuban <robert.kuban@opensynergy.com>
Approved-by: Razvan Deaconescu <razvand@unikraft.io>
GitHub-Closes: #1117
---

diff --git a/Makefile b/Makefile
index ad3af1d5e..8df14d93e 100644
--- a/Makefile
+++ b/Makefile
@@ -440,6 +440,7 @@ HOSTOBJCOPY	:= $(shell which $(HOSTOBJCOPY) || type -p $(HOSTOBJCOPY) || echo ob
 HOSTRANLIB	:= $(shell which $(HOSTRANLIB) || type -p $(HOSTRANLIB) || echo ranlib)
 HOSTCC_VERSION	:= $(shell $(HOSTCC_NOCCACHE) --version | \
 		   $(SED) -n -r 's/^.* ([0-9]*)\.([0-9]*)\.([0-9]*)[ ]*.*/\1 \2/p')
+HOSTUTC		:= $(shell date -u)
 HOSTNAME	:= $(shell hostname -s)
 HOSTUSER	:= $(shell whoami)
 
diff --git a/lib/uklibid/Config.uk b/lib/uklibid/Config.uk
index a8599cd07..ac96c3826 100644
--- a/lib/uklibid/Config.uk
+++ b/lib/uklibid/Config.uk
@@ -38,6 +38,13 @@ config LIBUKLIBID_INFO
 				used for during compilation for the unikernel
 				image.
 
+		config LIBUKLIBID_INFO_COMPILEDATE
+			bool "Compile date"
+			default y
+			help
+				This option stores the compile date and time for
+				the unikernel image.
+
 		config LIBUKLIBID_INFO_UKCONFIGGZ
 			bool "Embed gzipped configuration (.config)"
 			help
@@ -74,6 +81,12 @@ config LIBUKLIBID_INFO
 			help
 				Enables storing the C compiler ($(CC)) that was
 				used for each library.
+
+		config LIBUKLIBID_INFO_LIB_COMPILEDATE
+			bool "Compile date"
+			help
+				This option stores the compile date and time for
+				each library.
 	endmenu
 
 	menuconfig LIBUKLIBID_INFO_COMPILEDBY
diff --git a/lib/uklibid/Makefile.uk b/lib/uklibid/Makefile.uk
index 110b3c486..21fc52b9f 100644
--- a/lib/uklibid/Makefile.uk
+++ b/lib/uklibid/Makefile.uk
@@ -44,10 +44,14 @@ ASFLAGS += -D__LIBUKLIBID_COMPILER__="$(CC_INFO)"
 ASFLAGS-$(CONFIG_OPTIMIZE_PIE) += -D__LIBUKLIBID_COMPILEOPT_PIE__=1
 ASFLAGS-$(CONFIG_OPTIMIZE_LTO) += -D__LIBUKLIBID_COMPILEOPT_LTO__=1
 ASFLAGS-$(CONFIG_OPTIMIZE_DEADELIM) += -D__LIBUKLIBID_COMPILEOPT_DCE__=1
+# NOTE: We hand-over $(HOSTUTC) instead of using __DATE__ and __TIME__ in order
+#       to ensure recompilation of `libinfo.S` due to changed compile flags
+ASFLAGS-$(CONFIG_LIBUKLIBID_INFO_LIB_COMPILEDATE) += -D__LIBUKLIBID_UTCDATE__="$(HOSTUTC)"
 ASFLAGS-$(CONFIG_LIBUKLIBID_INFO_COMPILEDBY_HOST) += -D__LIBUKLIBID_COMPILEDBY_HOST__="$(HOSTUSER)@$(HOSTNAME)"
 LIBUKLIBID_SRCS-$(CONFIG_LIBUKLIBID_INFO) +=  $(LIBUKLIBID_BASE)/infosec.ld
 LIBUKLIBID_SRCS-$(CONFIG_LIBUKLIBID_INFO) += $(LIBUKLIBID_BASE)/libinfo.S|global
 LIBUKLIBID_LIBINFO_GLOBAL_FLAGS-y += -D__GLOBALINFO__
+LIBUKLIBID_LIBINFO_GLOBAL_FLAGS-$(CONFIG_LIBUKLIBID_INFO_COMPILEDATE) += -DUK_UTCDATE="$(HOSTUTC)"
 LIBUKLIBID_LIBINFO_GLOBAL_CDEPS-$(CONFIG_LIBUKLIBID_INFO_UKCONFIGGZ) += $(LIBUKLIBID_BUILD)/config.gz
 LIBUKLIBID_LIBINFO_GLOBAL_FLAGS-$(CONFIG_LIBUKLIBID_INFO_UKCONFIGGZ) += -DUK_CONFIGGZINC="$(LIBUKLIBID_BUILD)/config.gz"
 
diff --git a/lib/uklibid/libinfo.S b/lib/uklibid/libinfo.S
index 7178d1010..15e54ceeb 100644
--- a/lib/uklibid/libinfo.S
+++ b/lib/uklibid/libinfo.S
@@ -34,6 +34,10 @@
 	RECORD(UKLI_REC_COMPILER,
 	       .asciz STRINGIFY(__LIBUKLIBID_COMPILER__))
 #endif /* CONFIG_LIBUKLIBID_INFO_COMPILER */
+#if CONFIG_LIBUKLIBID_INFO_COMPILEDATE
+	RECORD(UKLI_REC_COMPILEDATE,
+	       .asciz STRINGIFY(UK_UTCDATE))
+#endif /* CONFIG_LIBUKLIBID_INFO_COMPILEDATE */
 #if CONFIG_LIBUKLIBID_INFO_UKCONFIGGZ
 	RECORD(UKLI_REC_UKCONFIGGZ,    .incbin STRINGIFY(UK_CONFIGGZINC))
 #endif /* CONFIG_LIBUKLIBID_INFO_UKCONFIGGZ */
@@ -56,6 +60,10 @@
 	RECORD(UKLI_REC_COMPILER,
 	       .asciz STRINGIFY(__LIBUKLIBID_COMPILER__))
 #endif /* CONFIG_LIBUKLIBID_INFO_COMPILER */
+#if CONFIG_LIBUKLIBID_INFO_LIB_COMPILEDATE
+	RECORD(UKLI_REC_COMPILEDATE,
+	       .asciz STRINGIFY(__LIBUKLIBID_UTCDATE__))
+#endif /* CONFIG_LIBUKLIBID_INFO_COMPILEDATE */
 	RECORD(UKLI_REC_COMPILEOPTS,   .__u32 (
 			(!(!__LIBUKLIBID_COMPILEOPT_PIE__) * UKLI_REC_CO_PIE) |\
 			(!(!__LIBUKLIBID_COMPILEOPT_DCE__) * UKLI_REC_CO_DCE) |\