1 files changed, 51 insertions, 1 deletions

diff --git a/cmds/incidentd/src/incidentd_util.cpp b/cmds/incidentd/src/incidentd_util.cpp
index 2415860572fb..fc7cec9dbb40 100644
--- a/cmds/incidentd/src/incidentd_util.cpp
+++ b/cmds/incidentd/src/incidentd_util.cpp
@@ -13,8 +13,13 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+#define DEBUG false
+#include "Log.h"
+
 #include "incidentd_util.h"
 
+#include <sys/prctl.h>
+
 #include "section_list.h"
 
 const Privacy* get_privacy_of_section(int id) {
@@ -50,4 +55,49 @@ bool Fpipe::init() { return Pipe(&mRead, &mWrite); }
 
 int Fpipe::readFd() const { return mRead.get(); }
 
-int Fpipe::writeFd() const { return mWrite.get(); }
\ No newline at end of file
+int Fpipe::writeFd() const { return mWrite.get(); }
+
+pid_t fork_execute_cmd(const char* cmd, char* const argv[], Fpipe* input, Fpipe* output) {
+    // fork used in multithreaded environment, avoid adding unnecessary code in child process
+    pid_t pid = fork();
+    if (pid == 0) {
+        if (TEMP_FAILURE_RETRY(dup2(input->readFd(), STDIN_FILENO)) < 0 || !input->close() ||
+            TEMP_FAILURE_RETRY(dup2(output->writeFd(), STDOUT_FILENO)) < 0 || !output->close()) {
+            ALOGW("Can't setup stdin and stdout for command %s", cmd);
+            _exit(EXIT_FAILURE);
+        }
+
+        /* make sure the child dies when incidentd dies */
+        prctl(PR_SET_PDEATHSIG, SIGKILL);
+
+        execv(cmd, argv);
+
+        ALOGW("%s failed in the child process: %s", cmd, strerror(errno));
+        _exit(EXIT_FAILURE);  // always exits with failure if any
+    }
+    // close the fds used in child process.
+    close(input->readFd());
+    close(output->writeFd());
+    return pid;
+}
+// ================================================================================
+const char** varargs(const char* first, va_list rest) {
+    va_list copied_rest;
+    int numOfArgs = 1;  // first is already count.
+
+    va_copy(copied_rest, rest);
+    while (va_arg(copied_rest, const char*) != NULL) {
+        numOfArgs++;
+    }
+    va_end(copied_rest);
+
+    // allocate extra 1 for NULL terminator
+    const char** ret = (const char**)malloc(sizeof(const char*) * (numOfArgs + 1));
+    ret[0] = first;
+    for (int i = 0; i < numOfArgs; i++) {
+        const char* arg = va_arg(rest, const char*);
+        ret[i + 1] = arg;
+    }
+    ret[numOfArgs + 1] = NULL;
+    return ret;
+}