# Copyright 1999-2017 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2

#
# Helper functions
#
function printn(string) {
	printf("%s", string)
}
function einfo(string) {
	printf(" \033[32;01m*\033[0m %s\n", string)
}
function einfon(string) {
	printf(" \033[32;01m*\033[0m %s", string)
}
function ewarn(string) {
	printf(" \033[33;01m*\033[0m %s\n", string)
}
function ewarnn(string) {
	printf(" \033[33;01m*\033[0m %s", string)
}
function eerror(string) {
	printf(" \033[31;01m*\033[0m %s\n", string)
}

#
# assert(condition, errmsg)
#   assert that a condition is true.  Otherwise exit.
#
function assert(condition, string) {
	if (! condition) {
		printf("%s:%d: assertion failed: %s\n",
		       FILENAME, FNR, string) > "/dev/stderr"
		_assert_exit = 1
		exit 1
	}
}

#
# system(command, return)
#   wrapper that normalizes return codes ...
#
function dosystem(command, ret) {
	ret = 0
	ret = system(command)
	if (ret == 0)
		return 1
	else
		return 0
}

BEGIN {
	#
	# Get our variables from environment
	#
	OLDVER = ENVIRON["OLDVER"]
	OLDCHOST = ENVIRON["OLDCHOST"]

	if (OLDVER == "") {
		eerror("Could not get OLDVER!");
		exit 1
	}

	# Setup some sane defaults
	LIBCOUNT = 2
	HAVE_GCC34 = 0
	DIRLIST[1] = "/lib"
	DIRLIST[2] = "/usr/lib"

	#
	# Walk /etc/ld.so.conf to discover all our library paths
	#
	pipe = "cat /etc/ld.so.conf | sort 2>/dev/null"
	while(((pipe) | getline ldsoconf_data) > 0) {
		if (ldsoconf_data !~ /^[[:space:]]*#/) {
			if (ldsoconf_data == "") continue

			# Remove any trailing comments
			sub(/#.*$/, "", ldsoconf_data)
			# Remove any trailing spaces
			sub(/[[:space:]]+$/, "", ldsoconf_data)

			# If there's more than one path per line, split 
			# it up as if they were sep lines
			split(ldsoconf_data, nodes, /[:,[:space:]]/)

			# Now add the rest from ld.so.conf
			for (x in nodes) {
				# wtf does this line do ?
				sub(/=.*/, "", nodes[x])
				# Prune trailing /
				sub(/\/$/, "", nodes[x])

				if (nodes[x] == "") continue

				#
				# Drop the directory if its a child directory of
				# one that was already added ...
				# For example, if we have:
				#   /usr/lib /usr/libexec /usr/lib/mozilla /usr/lib/nss
				# We really just want to save /usr/lib /usr/libexec
				#
				CHILD = 0
				for (y in DIRLIST) {
					if (nodes[x] ~ "^" DIRLIST[y] "(/|$)") {
						CHILD = 1
						break
					}
				}
				if (CHILD) continue

				DIRLIST[++LIBCOUNT] = nodes[x]
			}
		}
	}
	close(pipe)

	#
	# Get line from gcc's output containing CHOST
	#
	pipe = "gcc -print-file-name=libgcc.a 2>/dev/null"
	if ((!((pipe) | getline TMP_CHOST)) || (TMP_CHOST == "")) {
		close(pipe)

		# If we fail to get the CHOST, see if we can get the CHOST
		# portage thinks we are using ...
		pipe = "/usr/bin/portageq envvar 'CHOST'"
		assert(((pipe) | getline CHOST), "(" pipe ") | getline CHOST")
	} else {
		# Check pre gcc-3.4.x versions
		CHOST = gensub("^.+lib/gcc-lib/([^/]+)/[0-9]+.+$", "\\1", 1, TMP_CHOST)

		if (CHOST == TMP_CHOST || CHOST == "") {
			# Check gcc-3.4.x or later
			CHOST = gensub("^.+lib/gcc/([^/]+)/[0-9]+.+$", "\\1", 1, TMP_CHOST);

			if (CHOST == TMP_CHOST || CHOST == "")
				CHOST = ""
			else
				HAVE_GCC34 = 1
		}
	}
	close(pipe)

	if (CHOST == "") {
		eerror("Could not get gcc's CHOST!")
		exit 1
	}

	if (OLDCHOST != "")
		if (OLDCHOST == CHOST)
			OLDCHOST = ""

	GCCLIBPREFIX_OLD = "/usr/lib/gcc-lib/"
	GCCLIBPREFIX_NEW = "/usr/lib/gcc/"

	if (HAVE_GCC34)
		GCCLIBPREFIX = GCCLIBPREFIX_NEW
	else
		GCCLIBPREFIX = GCCLIBPREFIX_OLD

	GCCLIB = GCCLIBPREFIX CHOST

	if (OLDCHOST != "") {
		OLDGCCLIB1 = GCCLIBPREFIX_OLD OLDCHOST
		OLDGCCLIB2 = GCCLIBPREFIX_NEW OLDCHOST
	}

	# Get current gcc's version
	pipe = "gcc -dumpversion"
	assert(((pipe) | getline NEWVER), "(" pipe ") | getline NEWVER)")
	close(pipe)

	if (NEWVER == "") {
		eerror("Could not get gcc's version!")
		exit 1
	}

	# Nothing to do ?
	if ((OLDVER == NEWVER) && (OLDCHOST == ""))
		exit 0

	#
	# Ok, now let's scan for the .la files and actually fix them up
	#
	for (x = 1; x <= LIBCOUNT; x++) {
		# Do nothing if the target dir is gcc's internal library path
		if (DIRLIST[x] ~ GCCLIBPREFIX_OLD ||
		    DIRLIST[x] ~ GCCLIBPREFIX_NEW)
			continue

		einfo("  [" x "/" LIBCOUNT "] Scanning " DIRLIST[x] " ...")

		pipe = "find " DIRLIST[x] "/ -name '*.la' 2>/dev/null"
		while (((pipe) | getline la_files) > 0) {

			# Do nothing if the .la file is located in gcc's internal lib path
			if (la_files ~ GCCLIBPREFIX_OLD ||
			    la_files ~ GCCLIBPREFIX_NEW)
				continue

			CHANGED = 0
			CHOST_CHANGED = 0

			# See if we need to fix the .la file
			while ((getline la_data < (la_files)) > 0) {
				if (OLDCHOST != "") {
					if ((gsub(OLDGCCLIB1 "[/[:space:]]+",
					          GCCLIB, la_data) > 0) ||
					    (gsub(OLDGCCLIB2 "[/[:space:]]+",
					          GCCLIB, la_data) > 0)) {
						CHANGED = 1
						CHOST_CHANGED = 1
					}
				}
				if (OLDVER != NEWVER) {
					if ((gsub(GCCLIBPREFIX_OLD CHOST "/" OLDVER "[/[:space:]]*",
					          GCCLIB "/" NEWVER, la_data) > 0) ||
					    (gsub(GCCLIBPREFIX_NEW CHOST "/" OLDVER "[/[:space:]]*",
					          GCCLIB "/" NEWVER, la_data) > 0))
						CHANGED = 1
				}
			}
			close(la_files)

			# Do the actual changes in a second loop, as we can then
			# verify that CHOST_CHANGED among things is correct ...
			if (CHANGED) {
				ewarnn("    FIXING: " la_files " ...")

				if (CHANGED)
					printn("[")

				# Clear the temp file (removing rather than '>foo' is better
				# out of a security point of view?)
				dosystem("rm -f " la_files ".new")

				while ((getline la_data < (la_files)) > 0) {
					if (OLDCHOST != "") {
						tmpstr = gensub(OLDGCCLIB1 "([/[:space:]]+)",
						                GCCLIB "\\1", "g", la_data)
						tmpstr = gensub(OLDGCCLIB2 "([/[:space:]]+)",
						                GCCLIB "\\1", "g", tmpstr)

						if (la_data != tmpstr) {
							printn("c")
							la_data = tmpstr
						}

						if (CHOST_CHANGED > 0) {
							# We try to be careful about CHOST changes outside
							# the gcc library path (meaning we cannot match it
							# via /GCCLIBPREFIX CHOST/) ...

							# Catch:
							#
							#  dependency_libs=' -L/usr/CHOST/{bin,lib}'
							#
							gsub("-L/usr/" OLDCHOST "/",
							     "-L/usr/" CHOST "/", la_data)
							# Catch:
							#
							#  dependency_libs=' -L/usr/lib/gcc-lib/CHOST/VER/../../../../CHOST/lib'
							#
							la_data = gensub("(" GCCLIB "/[^[:space:]]+)/" OLDCHOST "/",
							                 "\\1/" CHOST "/", "g", la_data)
						}
					}

					if (OLDVER != NEWVER) {
						# Catch:
						#
						#  dependency_libs=' -L/usr/lib/gcc/CHOST/VER'
						#
						tmpstr = gensub(GCCLIBPREFIX_OLD CHOST "/" OLDVER "([/[:space:]]+)",
						                GCCLIB "/" NEWVER "\\1", "g", la_data)
						tmpstr = gensub(GCCLIBPREFIX_NEW CHOST "/" OLDVER "([/[:space:]]+)",
						                GCCLIB "/" NEWVER "\\1", "g", tmpstr)

						if (la_data != tmpstr) {
							# Catch:
							#
							#  dependency_libs=' -L/usr/lib/gcc-lib/../../CHOST/lib'
							#
							# in cases where we have gcc34
							tmpstr = gensub(GCCLIBPREFIX_OLD "(../../" CHOST "/lib)",
							                GCCLIBPREFIX "\\1", "g", tmpstr)
							tmpstr = gensub(GCCLIBPREFIX_NEW "(../../" CHOST "/lib)",
							                GCCLIBPREFIX "\\1", "g", tmpstr)
							printn("v")
							la_data = tmpstr
						}
					}

					print la_data >> (la_files ".new")
				}

				if (CHANGED)
					print "]"

				close(la_files)
				close(la_files ".new")

				assert(dosystem("mv -f " la_files ".new " la_files),
				       "dosystem(\"mv -f " la_files ".new " la_files "\")")
			}
		}

		close(pipe)
	}
}

# vim:ts=4