Initial Contribution

2 files changed, 133 insertions, 0 deletions

diff --git a/logwrapper/Android.mk b/logwrapper/Android.mk
new file mode 100644
index 0000000..5fd6356
--- /dev/null
+++ b/logwrapper/Android.mk
@@ -0,0 +1,7 @@
+LOCAL_PATH:= $(call my-dir)
+
+include $(CLEAR_VARS)
+LOCAL_SRC_FILES:= logwrapper.c
+LOCAL_MODULE := logwrapper
+LOCAL_STATIC_LIBRARIES := liblog
+include $(BUILD_EXECUTABLE)
diff --git a/logwrapper/logwrapper.c b/logwrapper/logwrapper.c
new file mode 100644
index 0000000..c7a2534
--- /dev/null
+++ b/logwrapper/logwrapper.c
@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <string.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "cutils/log.h"
+
+void fatal(const char *msg) {
+    fprintf(stderr, msg);
+    LOG(LOG_ERROR, "logwrapper", msg);
+    exit(-1);
+}
+
+void usage() {
+    fatal(
+        "Usage: logwrapper BINARY [ARGS ...]\n"
+        "\n"
+        "Forks and executes BINARY ARGS, redirecting stdout and stderr to\n"
+        "the Android logging system. Tag is set to BINARY, priority is\n"
+        "always LOG_INFO.\n");
+}
+
+void parent(const char *tag, int parent_read) {
+    int status;
+    char buffer[1024];
+
+    int a = 0;  // start index of unprocessed data
+    int b = 0;  // end index of unprocessed data
+    int sz;
+    while ((sz = read(parent_read, &buffer[b], 1023 - b)) > 0) {
+        // Log one line at a time
+        for (b = a; b < sz; b++) {
+            if (buffer[b] == '\n') {
+                buffer[b] = '\0';
+                LOG(LOG_INFO, tag, &buffer[a]);
+                a = b + 1;
+            }
+        }
+
+        if (a == 0 && b == 1023) {
+            // buffer is full, flush
+            buffer[b] = '\0';
+            LOG(LOG_INFO, tag, &buffer[a]);
+            b = 0;
+        } else {
+            // Keep left-overs
+            b = sz - a;
+            memmove(buffer, &buffer[a], b);
+            a = 0;
+        }
+    }
+    // Flush remaining data
+    if (a != b) {
+        buffer[b] = '\0';
+        LOG(LOG_INFO, tag, &buffer[a]);
+    }
+    wait(&status);  // Wait for child
+}
+
+void child(int argc, char* argv[]) {
+    // create null terminated argv_child array
+    char* argv_child[argc + 1];
+    memcpy(argv_child, argv, argc * sizeof(char *));
+    argv_child[argc] = NULL;
+
+    if (execvp(argv_child[0], argv_child)) {
+        LOG(LOG_ERROR, "logwrapper",
+            "executing %s failed: %s\n", argv_child[0], strerror(errno));
+        exit(-1);
+    }
+}
+
+int main(int argc, char* argv[]) {
+    pid_t pid;
+
+    int pipe_fds[2];
+    int *parent_read = &pipe_fds[0];
+    int *child_write = &pipe_fds[1];
+
+    if (argc < 2) {
+        usage();
+    }
+
+    if (pipe(pipe_fds) < 0) {
+        fatal("Cannot create pipe\n");
+    }
+
+    pid = fork();
+    if (pid < 0) {
+        fatal("Failed to fork\n");
+    } else if (pid == 0) {
+        // redirect stdout and stderr
+        close(*parent_read);
+        dup2(*child_write, 1);
+        dup2(*child_write, 2);
+        close(*child_write);
+
+        child(argc - 1, &argv[1]);
+
+    } else {
+        close(*child_write);
+
+        parent(argv[1], *parent_read);
+    }
+
+    return 0;
+}