Automated g4 rollback of commit 3e5edaf.

*** Reason for rollback ***

Likely cause for b/38172480 ("blaze now waits for all processes spawned by local tests to terminate") and b/38194553 ("Server terminated abruptly (error code: 14, error message: 'Endpoint read failed'").

I have a fix almost ready, but it consists of many lines of new code - we shouldn't rush that into Bazel's 0.5.0 release. Instead, let's roll this back, do a release using the known good older process-wrapper and then go forward in 0.5.1 with a better and well tested new version of this.

*** Original change description ***

process-wrapper: Wait for all (grand)children before exiting.

This uses Linux's PR_SET_CHILD_SUBREAPER and FreeBSD's PROC_REAP_ACQUIRE features to become an init-like process for all (grand)children spawned by process-wrapper, which allows us to a) kill them reliably and then b) wait for them reliably. Before this change, we only killed the main child, waited for it, then fired off a kill -9 on the process group, without waiting for it. This led to a race condition where Bazel would try to use...

***

PiperOrigin-RevId: 156068188

src/main/tools/BUILD

@@ -1,28 +1,20 @@
 package(default_visibility = ["//src:__subpackages__"])
 
-cc_library(
-    name = "process-tools",
-    srcs = [
-        "process-tools.cc",
-        "process-tools.h",
-    ],
-)
-
 cc_binary(
     name = "process-wrapper",
     srcs = select({
         "//src:windows_msvc": ["process-wrapper-windows.cc"],
         "//conditions:default": [
-            "process-wrapper.cc",
+            "process-tools.c",
+            "process-tools.h",
+            "process-wrapper.c",
         ],
     }),
-    linkopts = ["-lm"],
-    deps = select({
+    copts = select({
         "//src:windows_msvc": [],
-        "//conditions:default": [
-            ":process-tools",
-        ],
+        "//conditions:default": ["-std=c99"],
     }),
+    linkopts = ["-lm"],
 )
 
 cc_binary(
@@ -53,17 +45,6 @@ cc_binary(
         ],
     }),
     linkopts = ["-lm"],
-    deps = select({
-        "//src:darwin": [],
-        "//src:darwin_x86_64": [],
-        "//src:freebsd": [],
-        "//src:windows": [],
-        "//src:windows_msys": [],
-        "//src:windows_msvc": [],
-        "//conditions:default": [
-            ":process-tools",
-        ],
-    }),
 )
 
 filegroup(

src/main/tools/linux-sandbox-options.cc

@@ -12,13 +12,14 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include "src/main/tools/linux-sandbox-options.h"
+#include "linux-sandbox-options.h"
+#include "linux-sandbox-utils.h"
 
 #define DIE(args...)                                     \
   {                                                      \
     fprintf(stderr, __FILE__ ":" S__LINE__ ": \"" args); \
     fprintf(stderr, "\": ");                             \
-    perror(nullptr);                                     \
+    perror(NULL);                                        \
     exit(EXIT_FAILURE);                                  \
   }
 
@@ -38,8 +39,6 @@
 #include <string>
 #include <vector>
 
-#include "src/main/tools/linux-sandbox-utils.h"
-
 using std::ifstream;
 using std::unique_ptr;
 using std::vector;
@@ -200,7 +199,6 @@ static void ParseCommandLine(unique_ptr<vector<char *>> args) {
   if (optind < static_cast<int>(args->size())) {
     if (opt.args.empty()) {
       opt.args.assign(args->begin() + optind, args->end());
-      opt.args.push_back(nullptr);
     } else {
       Usage(args->front(), "Merging commands not supported.");
     }
@@ -209,8 +207,8 @@ static void ParseCommandLine(unique_ptr<vector<char *>> args) {
 
 // Expands a single argument, expanding options @filename to read in the content
 // of the file and add it to the list of processed arguments.
-static unique_ptr<vector<char *>> ExpandArgument(
-    unique_ptr<vector<char *>> expanded, char *arg) {
+unique_ptr<vector<char *>> ExpandArgument(unique_ptr<vector<char *>> expanded,
+                                          char *arg) {
   if (arg[0] == '@') {
     const char *filename = arg + 1;  // strip off the '@'.
     ifstream f(filename);
@@ -238,7 +236,7 @@ static unique_ptr<vector<char *>> ExpandArgument(
 // Pre-processes an argument list, expanding options @filename to read in the
 // content of the file and add it to the list of arguments. Stops expanding
 // arguments once it encounters "--".
-static unique_ptr<vector<char *>> ExpandArguments(const vector<char *> &args) {
+unique_ptr<vector<char *>> ExpandArguments(const vector<char *> &args) {
   unique_ptr<vector<char *>> expanded(new vector<char *>());
   expanded->reserve(args.size());
   for (auto arg = args.begin(); arg != args.end(); ++arg) {
@@ -262,6 +260,6 @@ void ParseOptions(int argc, char *argv[]) {
   }
 
   if (opt.working_dir.empty()) {
-    opt.working_dir = getcwd(nullptr, 0);
+    opt.working_dir = getcwd(NULL, 0);
   }
 }