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-rw-r--r--.gitignore3
-rw-r--r--Makefile8
-rw-r--r--README69
-rwxr-xr-xgcc-config33
-rw-r--r--tests/rw-multi-native-configs/test.select4
-rwxr-xr-xtests/rw-multi-native-configs/usr/lib/gcc-config/wrapper0
-rw-r--r--tests/source/test.whitespace2
-rw-r--r--wrapper.c323
8 files changed, 28 insertions, 414 deletions
diff --git a/.gitignore b/.gitignore
index 23938ed..b79124b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,4 @@
-a.out
*~
-*.o
*.diff
*.patch
@@ -10,4 +8,3 @@ a.out
/gcc-config-*.tar.*
/.gcc-config
-/wrapper
diff --git a/Makefile b/Makefile
index 3cbb915..3e9e5a3 100644
--- a/Makefile
+++ b/Makefile
@@ -13,16 +13,15 @@ BINDIR = $(PREFIX)/bin
ESELECTDIR = $(PREFIX)/share/eselect/modules
SUBLIBDIR = lib
LIBDIR = $(PREFIX)/$(SUBLIBDIR)
-LIBEXECDIR = $(LIBDIR)/$(PN)
MKDIR_P = mkdir -p -m 755
INSTALL_EXE = install -m 755
INSTALL_DATA = install -m 644
-all: .gcc-config wrapper
+all: .gcc-config
clean:
- rm -f .gcc-config wrapper *.o core
+ rm -f .gcc-config
.gcc-config: gcc-config
sed \
@@ -34,8 +33,7 @@ clean:
chmod a+rx $@
install: all
- $(MKDIR_P) $(DESTDIR)$(BINDIR) $(DESTDIR)$(LIBEXECDIR) $(DESTDIR)$(ESELECTDIR)
- $(INSTALL_EXE) wrapper $(DESTDIR)$(LIBEXECDIR)/wrapper
+ $(MKDIR_P) $(DESTDIR)$(BINDIR) $(DESTDIR)$(ESELECTDIR)
$(INSTALL_EXE) .gcc-config $(DESTDIR)$(BINDIR)/gcc-config
$(INSTALL_DATA) gcc.eselect $(DESTDIR)$(ESELECTDIR)
diff --git a/README b/README
index e7933d8..bea5e30 100644
--- a/README
+++ b/README
@@ -6,20 +6,18 @@ Gentoo allows switching gcc as system runs via gcc-config:
$ gcc-config x86_64-pc-linux-gnu-7.2.0
Ideally changes should be visible instantly and atomically
-without shell restart. Practically see TODOs and BUGs on PATH/ROOTPATH.
+without shell restart.
Files, variables, things.
-------------------------
-- Wrappers (copies of /usr/$(libexec)/gcc-config/wrapper)
- /usr/bin/gcc
- /usr/bin/g++
- /usr/bin/${CTARGET}-gcc
+- Wrappers (symlinks to compiler binary like /usr/${CTARGET}/gcc-bin/${GCC_VERSION}/gcc)
+ /usr/bin/gcc (native)
+ /usr/bin/g++ (native)
+ /usr/bin/${CTARGET}-gcc (native and cross)
...
(all files from /usr/${CTARGET}/gcc-bin/$GCC_VERSION/*)
- Wrapper reads env config and re-execs binary from `GCC_PATH`.
-
See `gcc-config` script for wrapping details.
- private gcc configs (provided by `toolchain.eclass`, gcc ebuilds)
@@ -39,7 +37,6 @@ Files, variables, things.
GCC_PATH="/usr/x86_64-pc-linux-gnu/gcc-bin/8.1.0"
Used by gcc-config to generate wrappers and 05gcc- env.d files.
- Used by wrapper to extract GCC_PATH and re-exec().
- gcc env.d compiler entries (provided by gcc-config)
@@ -47,8 +44,6 @@ Files, variables, things.
Populates paths for native-compilers
- PATH="/usr/x86_64-pc-linux-gnu/gcc-bin/8.2.0"
- ROOTPATH="/usr/x86_64-pc-linux-gnu/gcc-bin/8.2.0"
GCC_SPECS=""
MANPATH="/usr/share/gcc-data/x86_64-pc-linux-gnu/8.2.0/man"
INFOPATH="/usr/share/gcc-data/x86_64-pc-linux-gnu/8.2.0/info"
@@ -57,60 +52,16 @@ Files, variables, things.
/etc/env.d/05gcc-${CTARGET} (cross)
- Populates paths for cross-compilers
-
- PATH="/usr/x86_64-pc-linux-gnu/powerpc64le-unknown-linux-gnu/gcc-bin/7.3.0"
- ROOTPATH="/usr/x86_64-pc-linux-gnu/powerpc64le-unknown-linux-gnu/gcc-bin/7.3.0"
-
- Used by wrapper to extract PATH and re-exec().
- Used by env-update to populate PATH (TODO: remove PATH population).
-
-How does gcc-config work?
--------------------------
-
-/usr/bin/gcc (or /usr/bin/<tool>) is a wrapper (wrapper.c).
-gcc-config allows runtime gcc switch via level of indirection.
-
-Tool name is ${CTARGET}-<tool> or <tool>. TODO: doesn't it break
-on ${CTARGET}-<tool>-<version>? Doesn't ${CTARGET} get misdetected?
-
-Today's resolution order is the following:
+ Empty.
-1. Searches PATH for <tool> and reexecute if found. Some
- target paths are ignored:
- - itself (/usr/bin/<tool>) is ignored to avoid recursion
- - */gcc-bin/* (/usr/${CHOST}/${CTARGET}/gcc-bin/7.3.0) is ignored
- as those should precede in PATH to avoid wrapping entirely or be
- selected via gcc-config.
-2. If [1.] failed search for /etc/env.d/: /etc/env.d/gcc/.NATIVE (native compiler),
- /etc/env.d/05gcc-${CTARGET} (cross-compiler).
-
- There GCC_PATH= (native) or PATH= (cross) directory entry is searched.
-
- Usually it's GCC_PATH="${EPREFIX}/usr/${CHOST}/gcc-bin/<gcc-version>" (native)
- or GCC_PATH="${EPREFIX}/usr/${CHOST}/${CTARGET}/gcc-bin/<gcc-version>" (cross)
-
-3. If [2.] failed run 'ROOT= gcc-config --get-bin-path' and use it's output.
-
-4. Prepend path fetched from above to PATH environment variable and re-exec().
-
-5. Done
-
-`gcc-config` script maintains binaries in `/usr/bin/` to make the above model work.
-
-To make compiler switchable in active shell `/usr/bin/` path must precede
-'/usr/${CHOST}/gcc-bin/<gcc-version>'. Otherwise wrapper is skipped.
+ Until Aug 2018 used to contain paths for cross-compilers.
+ To be removed eventually.
TODOs
-----
- Write proper `gcc-config` manpage off this readme to be more discoverable.
-- Make /usr/bin/<tool> a symlink of /usr/$(libexec)/gcc-config/wrapper,
- not a file copy. This will make the fact that Gentoo uses wrappers more obvious.
- It's essential to know for people using ccache cache or similar.
-
-- Move /etc/env.d/05gcc-${CTARGET} and /etc/env.d/04gcc-${CTARGET} after
- /usr/bin PATH injection to restore gcc-config wrapping.
+- Figure out symlink ownership story. Today symlinks don't belong to any package.
- See https://bugs.gentoo.org/255695 for some details.
+ See https://bugs.gentoo.org/626606
diff --git a/gcc-config b/gcc-config
index 521e3ba..e7f3fb9 100755
--- a/gcc-config
+++ b/gcc-config
@@ -167,16 +167,14 @@ convert_profile_paths() {
return 0
}
-# Usage: atomic_cp <source file> <destination dir> <destination file name> <reference file (mtimes)>
-atomic_cp() {
- local src=$1 dst=$2 dstfile=$3 ref=$4 tmp
+# Usage: atomic_ln <source file> <destination dir> <destination file name>
+atomic_ln() {
+ local src=$1 dst=$2 dstfile=$3 tmp
tmp="${dst}/.gcc.config.${dstfile}"
- # We need to do this mv to make the update atomic in case
- # someone is compiling at the same time they're running
- # gcc-config (which is OK if you're just updating gcc-config
- # itself and picking the same profile).
- cp -f "${src}" "${tmp}"
- touch -r "${ref}" "${tmp}"
+ # `ln` will expand into unlink();symlink(); which
+ # is not atomic for a small amount of time, but
+ # `mv` is a single rename() call
+ ln -sf "${src}" "${tmp}"
mv "${tmp}" "${dst}/${dstfile}"
}
@@ -197,13 +195,6 @@ update_wrappers() {
# for new functionality (like a version bump).
local x CTARGET=$1
- # Find the bin wrapper
- local libdir wrapper
- for libdir in ${GENTOO_LIBDIR} lib lib64 lib32 lib ; do
- wrapper="${EROOT}usr/${libdir}/gcc-config/wrapper"
- [[ -e ${wrapper} ]] && break
- done
-
# Use the old dir to see what we wrapped up previously.
local old_wrappers=( $(
[[ -n ${OLD_GCC_PATH} ]] || exit 1
@@ -261,9 +252,9 @@ update_wrappers() {
fi
fi
- # Now do the actual wrapper copy with paths to the reference binary
+ # Now do the actual linking to the target binary
if [[ -x ${ref} ]] ; then
- atomic_cp "${wrapper}" "${EROOT}usr/bin" "${x}" "${ref}"
+ atomic_ln "${ref#${ROOT}}" "${EROOT}usr/bin" "${x}"
else
ewarn "double insanity with ${x} and ${ref}"
# Make sure we have no stale wrappers
@@ -275,7 +266,7 @@ update_wrappers() {
# install the canonical cpp wrapper
if ! is_cross_compiler ; then
- atomic_cp "${wrapper}" "${EROOT}lib" "cpp" "${EROOT}usr/bin/cpp"
+ atomic_ln "${EPREFIX%/}/usr/bin/cpp" "${EROOT}lib" "cpp"
fi
}
@@ -619,8 +610,7 @@ switch_profile() {
is_cross_compiler && envd_num="05" || envd_num="04"
envd="${ENV_D}/${envd_num}gcc-${CTARGET}"
cat <<-EOF > "${envd}.tmp"
- PATH="${GCC_PATH}"
- ROOTPATH="${GCC_PATH}"
+ # Autogenerated by 'gcc-config'.
EOF
if ! is_cross_compiler ; then
# Only write GCC_SPECS for the native compiler. #420097
@@ -724,6 +714,7 @@ switch_profile() {
eend 0
+ # Not needed since Aug 2018. Can be removed later (say, in a year).
if [[ ${envd_changed} -ne 0 ]] ; then
echo
ewarn "If you intend to use the gcc from the new profile in an already"
diff --git a/tests/rw-multi-native-configs/test.select b/tests/rw-multi-native-configs/test.select
index c6d9daf..a9cc1d1 100644
--- a/tests/rw-multi-native-configs/test.select
+++ b/tests/rw-multi-native-configs/test.select
@@ -18,10 +18,10 @@ for (( i = 1; i < 4; ++i )) ; do
esac
for b in "${do_want[@]}" ; do
- [[ -e usr/bin/${b} ]] || exit 1
+ [[ -L usr/bin/${b} ]] || exit 1
done
for b in "${dont_want[@]}" ; do
- [[ -e usr/bin/${b} ]] && exit 1
+ [[ -L usr/bin/${b} ]] && exit 1
done
[[ -e etc/env.d/04gcc-${CHOST} ]] || exit 1
done
diff --git a/tests/rw-multi-native-configs/usr/lib/gcc-config/wrapper b/tests/rw-multi-native-configs/usr/lib/gcc-config/wrapper
deleted file mode 100755
index e69de29..0000000
--- a/tests/rw-multi-native-configs/usr/lib/gcc-config/wrapper
+++ /dev/null
diff --git a/tests/source/test.whitespace b/tests/source/test.whitespace
index 28108ae..26d1bdb 100644
--- a/tests/source/test.whitespace
+++ b/tests/source/test.whitespace
@@ -1,2 +1,2 @@
#!/bin/bash
-! egrep -nH '[[:space:]]+$' "${TROOT}"/../{gcc-config,wrapper.c}
+! egrep -nH '[[:space:]]+$' "${TROOT}"/../gcc-config
diff --git a/wrapper.c b/wrapper.c
deleted file mode 100644
index c245dbb..0000000
--- a/wrapper.c
+++ /dev/null
@@ -1,323 +0,0 @@
-/*
- * Copyright 1999-2012 Gentoo Foundation
- * Distributed under the terms of the GNU General Public License v2
- * Author: Martin Schlemmer <azarah@gentoo.org>
- * az's lackey: Mike Frysinger <vapier@gentoo.org>
- */
-
-#ifdef DEBUG
-# define USE_DEBUG 1
-#else
-# define USE_DEBUG 0
-#endif
-
-#ifndef _FILE_OFFSET_BITS
-# define _FILE_OFFSET_BITS 64 /* #471024 */
-#endif
-
-#include <errno.h>
-#include <libgen.h>
-#include <limits.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-
-#ifndef EPREFIX
-# define EPREFIX ""
-#endif
-
-#define GCC_CONFIG EPREFIX "/usr/bin/gcc-config"
-#define ENVD_BASE EPREFIX "/etc/env.d/05gcc"
-
-#define ARRAY_SIZE(arr) (sizeof(arr)/sizeof(arr[0]))
-
-/* basename(3) is allowed to modify memory */
-#undef basename
-#define basename(path) \
-({ \
- char *__path = path; \
- char *__ret = strrchr(__path, '/'); \
- __ret ? __ret + 1 : __path; \
-})
-
-struct wrapper_data {
- const char *name;
- char *fullname, *bin, *path;
-};
-
-static const struct {
- const char *alias;
- const char *target;
-} wrapper_aliases[] = {
- { "cc", "gcc" },
- { "f77", "gfortran" },
- { "f95", "gfortran" },
-};
-
-#define wrapper_warn(fmt, ...) fprintf(stderr, "%s" fmt "\n", "gcc-config: ", ## __VA_ARGS__)
-#define wrapper_err(fmt, ...) ({ wrapper_warn("%s" fmt, "error: ", ## __VA_ARGS__); exit(1); })
-#define wrapper_errp(fmt, ...) wrapper_err(fmt ": %s", ## __VA_ARGS__, strerror(errno))
-#define wrapper_dbg(fmt, ...) ({ if (USE_DEBUG) wrapper_warn(fmt, ## __VA_ARGS__); })
-
-#define xmemwrap(func, proto, use) \
-static void *x ## func proto \
-{ \
- void *ret = func use; \
- if (!ret) \
- wrapper_err(#func "%s", ": out of memory"); \
- return ret; \
-}
-xmemwrap(malloc, (size_t size), (size))
-xmemwrap(strdup, (const char *s), (s))
-
-/* check_for_target checks in path for the file we are seeking
- * it returns 1 if found (with data->bin setup), 0 if not and
- * negative on error
- */
-static int check_for_target(char *path, struct wrapper_data *data)
-{
- struct stat sbuf;
- char str[PATH_MAX + 1];
- size_t path_len = strlen(path);
- size_t len = path_len + strlen(data->name) + 2;
-
- if (sizeof(str) < len)
- wrapper_warn("path too long: %s", path);
-
- strcpy(str, path);
- str[path_len] = '/';
- str[path_len+1] = '\0';
- strcat(str, data->name);
-
- /* Stat possible file to check that
- * 1) it exist and is a regular file, and
- * 2) it is not the wrapper itself, and
- * 3) it is in a /gcc-bin/ directory tree
- */
- if (strcmp(str, data->fullname) != 0 &&
- strstr(str, "/gcc-bin/") != NULL &&
- stat(str, &sbuf) == 0 &&
- (S_ISREG(sbuf.st_mode) || S_ISLNK(sbuf.st_mode)))
- {
- wrapper_dbg("%s: found in %s", data->name, path);
- data->bin = xstrdup(str);
- return 1;
- }
-
- wrapper_dbg("%s: did not find in %s", data->name, path);
- return 0;
-}
-
-static int find_target_in_path(struct wrapper_data *data)
-{
- char *token = NULL, *state = NULL;
- char *str;
-
- if (data->path == NULL)
- return 0;
-
- /* Make a copy since strtok_r will modify path */
- str = xstrdup(data->path);
-
- /* Find the first file with suitable name in PATH. The idea here is
- * that we do not want to bind ourselfs to something static like the
- * default profile, or some odd environment variable, but want to be
- * able to build something with a non default gcc by just tweaking
- * the PATH ... */
- token = strtok_r(str, ":", &state);
- while (token != NULL) {
- if (check_for_target(token, data))
- return 1;
- token = strtok_r(NULL, ":", &state);
- }
-
- wrapper_dbg("%s: did not find in PATH", data->name);
- return 0;
-}
-
-/* find_target_in_envd parses /etc/env.d/05gcc, and tries to
- * extract PATH, which is set to the current profile's bin
- * directory ...
- */
-static int find_target_in_envd(struct wrapper_data *data, int cross_compile)
-{
- FILE *envfile = NULL;
- char *token = NULL, *state;
- char str[PATH_MAX + 1];
- char *strp = str;
- char envd_file[PATH_MAX + 1];
-
- if (!cross_compile) {
- /* for the sake of speed, we'll keep a symlink around for
- * the native compiler. #190260
- */
- snprintf(envd_file, sizeof(envd_file)-1, EPREFIX "/etc/env.d/gcc/.NATIVE");
- } else {
- char *ctarget, *end = strrchr(data->name, '-');
- if (end == NULL)
- return 0;
- ctarget = xstrdup(data->name);
- ctarget[end - data->name] = '\0';
- snprintf(envd_file, PATH_MAX, "%s-%s", ENVD_BASE, ctarget);
- free(ctarget);
- }
-
- envfile = fopen(envd_file, "r");
- if (envfile == NULL)
- return 0;
-
- while (fgets(strp, PATH_MAX, envfile) != NULL) {
- /* Keep reading ENVD_FILE until we get a line that
- * starts with 'GCC_PATH=' ... keep 'PATH=' around
- * for older gcc versions.
- */
- if (strncmp(strp, "GCC_PATH=", strlen("GCC_PATH=")) &&
- strncmp(strp, "PATH=", strlen("PATH=")))
- continue;
-
- token = strtok_r(strp, "=", &state);
- if ((token != NULL) && token[0])
- /* The second token should be the value of PATH .. */
- token = strtok_r(NULL, "=", &state);
- else
- goto bail;
-
- if ((token != NULL) && token[0]) {
- strp = token;
- /* A bash variable may be unquoted, quoted with " or
- * quoted with ', so extract the value without those ..
- */
- token = strtok(strp, "\n\"\'");
-
- while (token != NULL) {
- if (check_for_target(token, data)) {
- fclose(envfile);
- return 1;
- }
-
- token = strtok(NULL, "\n\"\'");
- }
- }
-
- strp = str;
- }
-
- bail:
- fclose(envfile);
- return (cross_compile ? 0 : find_target_in_envd(data, 1));
-}
-
-static void find_wrapper_target(struct wrapper_data *data)
-{
- if (find_target_in_path(data))
- return;
-
- if (find_target_in_envd(data, 0))
- return;
-
- /* Only our wrapper is in PATH, so get the CC path using
- * gcc-config and execute the real binary in there ...
- */
- FILE *inpipe = popen("ROOT= " GCC_CONFIG " --get-bin-path", "r");
- if (inpipe == NULL)
- wrapper_errp("could not open pipe");
-
- char str[PATH_MAX + 1];
- if (fgets(str, PATH_MAX, inpipe) == 0)
- wrapper_errp("could not get compiler binary path");
-
- /* chomp! */
- size_t plen = strlen(str);
- if (str[plen-1] == '\n')
- str[plen-1] = '\0';
-
- data->bin = xmalloc(plen + 1 + strlen(data->name) + 1);
- sprintf(data->bin, "%s/%s", str, data->name);
-
- pclose(inpipe);
-}
-
-/* This function modifies PATH to have gcc's bin path appended */
-static void modify_path(struct wrapper_data *data)
-{
- char *newpath = NULL, *token = NULL, *state;
- char dname_data[PATH_MAX + 1], str[PATH_MAX + 1];
- char *str2 = dname_data, *dname = dname_data;
- size_t len = 0;
-
- if (data->bin == NULL)
- return;
-
- if (data->path == NULL)
- return;
-
- snprintf(str2, PATH_MAX + 1, "%s", data->bin);
-
- if ((dname = dirname(str2)) == NULL)
- return;
-
- /* Make a copy since strtok_r will modify path */
- snprintf(str, PATH_MAX + 1, "%s", data->path);
-
- token = strtok_r(str, ":", &state);
-
- /* Check if we already appended our bin location to PATH */
- if ((token != NULL) && token[0])
- if (!strcmp(token, dname))
- return;
-
- len = strlen(dname) + strlen(data->path) + 2 + strlen("PATH") + 1;
-
- newpath = xmalloc(len);
- memset(newpath, 0, len);
-
- snprintf(newpath, len, "PATH=%s:%s", dname, data->path);
- putenv(newpath);
-}
-
-int main(int argc, char *argv[])
-{
- struct wrapper_data data;
- (void)argc; /* unused variable */
-
- memset(&data, 0, sizeof(data));
-
- if (getenv("PATH"))
- data.path = xstrdup(getenv("PATH"));
-
- /* What should we find ? */
- data.name = basename(argv[0]);
-
- /* Allow for common compiler names like cc->gcc */
- size_t i;
- for (i = 0; i < ARRAY_SIZE(wrapper_aliases); ++i)
- if (!strcmp(data.name, wrapper_aliases[i].alias))
- data.name = wrapper_aliases[i].target;
-
- /* What is the full name of our wrapper? */
- data.fullname = xmalloc(strlen(data.name) + sizeof(EPREFIX "/usr/bin/") + 1);
- sprintf(data.fullname, EPREFIX "/usr/bin/%s", data.name);
-
- find_wrapper_target(&data);
-
- modify_path(&data);
-
- free(data.path);
- data.path = NULL;
-
- /* Set argv[0] to the correct binary, else gcc can't find internal headers
- * http://bugs.gentoo.org/8132
- */
- argv[0] = data.bin;
-
- /* Ok, lets do it one more time ... */
- execv(data.bin, argv);
-
- /* shouldn't have made it here if things worked ... */
- wrapper_err("could not run/locate '%s'", data.name);
-
- return 123;
-}