firmware_handler: extract part responsible for running ext program to lib
As a preparation for upcoming commit, extract part which is responsible
for external program execution to libmodprobe so it can be later
re-used not only for firmware handler but also for dynamic module
options handler within libmodprobe.
RunExternalHandler is moved entirely to separate library with two
changes:
- Setting env needed previously by firmware handler was made generic and
now external handler can get envs_map containing pairs of env and its
value which needs to be set.
- "Firmware" was removed from one of the log since now it can be used in
different context (s/External Firmware Handler/External Handler/)
Bug: 335619610
Test: `atest CtsInitTestCases` passed, especially:
[105/129] ueventd_parser#ExternalFirmwareHandlers: PASSED (0ms)
[106/129] ueventd_parser#ExternalFirmwareHandlersDuplicate: PASSED (0ms)
Change-Id: Ie07cee763278f224bd3c0acfbe06c44eb36d0a81
diff --git a/init/firmware_handler.cpp b/init/firmware_handler.cpp
index 01957ef..dcfda52 100644
--- a/init/firmware_handler.cpp
+++ b/init/firmware_handler.cpp
@@ -38,6 +38,8 @@
#include <android-base/strings.h>
#include <android-base/unique_fd.h>
+#include "exthandler/exthandler.h"
+
using android::base::ReadFdToString;
using android::base::Socketpair;
using android::base::Split;
@@ -136,100 +138,6 @@
: firmware_directories_(std::move(firmware_directories)),
external_firmware_handlers_(std::move(external_firmware_handlers)) {}
-Result<std::string> FirmwareHandler::RunExternalHandler(const std::string& handler, uid_t uid,
- gid_t gid, const Uevent& uevent) const {
- unique_fd child_stdout;
- unique_fd parent_stdout;
- if (!Socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, &child_stdout, &parent_stdout)) {
- return ErrnoError() << "Socketpair() for stdout failed";
- }
-
- unique_fd child_stderr;
- unique_fd parent_stderr;
- if (!Socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, &child_stderr, &parent_stderr)) {
- return ErrnoError() << "Socketpair() for stderr failed";
- }
-
- signal(SIGCHLD, SIG_DFL);
-
- auto pid = fork();
- if (pid < 0) {
- return ErrnoError() << "fork() failed";
- }
-
- if (pid == 0) {
- setenv("FIRMWARE", uevent.firmware.c_str(), 1);
- setenv("DEVPATH", uevent.path.c_str(), 1);
- parent_stdout.reset();
- parent_stderr.reset();
- close(STDOUT_FILENO);
- close(STDERR_FILENO);
- dup2(child_stdout.get(), STDOUT_FILENO);
- dup2(child_stderr.get(), STDERR_FILENO);
-
- auto args = Split(handler, " ");
- std::vector<char*> c_args;
- for (auto& arg : args) {
- c_args.emplace_back(arg.data());
- }
- c_args.emplace_back(nullptr);
-
- if (gid != 0) {
- if (setgid(gid) != 0) {
- fprintf(stderr, "setgid() failed: %s", strerror(errno));
- _exit(EXIT_FAILURE);
- }
- }
-
- if (setuid(uid) != 0) {
- fprintf(stderr, "setuid() failed: %s", strerror(errno));
- _exit(EXIT_FAILURE);
- }
-
- execv(c_args[0], c_args.data());
- fprintf(stderr, "exec() failed: %s", strerror(errno));
- _exit(EXIT_FAILURE);
- }
-
- child_stdout.reset();
- child_stderr.reset();
-
- int status;
- pid_t waited_pid = TEMP_FAILURE_RETRY(waitpid(pid, &status, 0));
- if (waited_pid == -1) {
- return ErrnoError() << "waitpid() failed";
- }
-
- std::string stdout_content;
- if (!ReadFdToString(parent_stdout.get(), &stdout_content)) {
- return ErrnoError() << "ReadFdToString() for stdout failed";
- }
-
- std::string stderr_content;
- if (ReadFdToString(parent_stderr.get(), &stderr_content)) {
- auto messages = Split(stderr_content, "\n");
- for (const auto& message : messages) {
- if (!message.empty()) {
- LOG(ERROR) << "External Firmware Handler: " << message;
- }
- }
- } else {
- LOG(ERROR) << "ReadFdToString() for stderr failed";
- }
-
- if (WIFEXITED(status)) {
- if (WEXITSTATUS(status) == EXIT_SUCCESS) {
- return Trim(stdout_content);
- } else {
- return Error() << "exited with status " << WEXITSTATUS(status);
- }
- } else if (WIFSIGNALED(status)) {
- return Error() << "killed by signal " << WTERMSIG(status);
- }
-
- return Error() << "unexpected exit status " << status;
-}
-
std::string FirmwareHandler::GetFirmwarePath(const Uevent& uevent) const {
for (const auto& external_handler : external_firmware_handlers_) {
if (external_handler.match(uevent.path)) {
@@ -237,11 +145,15 @@
<< "' for devpath: '" << uevent.path << "' firmware: '" << uevent.firmware
<< "'";
+ std::unordered_map<std::string, std::string> envs_map;
+ envs_map["FIRMWARE"] = uevent.firmware;
+ envs_map["DEVPATH"] = uevent.path;
+
auto result = RunExternalHandler(external_handler.handler_path, external_handler.uid,
- external_handler.gid, uevent);
+ external_handler.gid, envs_map);
if (!result.ok() && NeedsRerunExternalHandler()) {
auto res = RunExternalHandler(external_handler.handler_path, external_handler.uid,
- external_handler.gid, uevent);
+ external_handler.gid, envs_map);
result = std::move(res);
}
if (!result.ok()) {