liblog: add logprint to host build

- cleanup of some style issues
- resolve a few minor bugs
- add -lrt for host so that clock_gettime can be issued
- enable write-only logging, logprint and event list
  handling tests for host consumption.

NB: CtsLiblogTestCases_list is only outlet for host testing of
    the interfaces, but it is not part of any automated testing

Test: gTest liblog-unit-tests, liblog-benchmarks and
      CtsLiblogTestCases_list && build mmma system/core/liblog
Bug: 27405083
Change-Id: I13db1f45f67569407587a5a909248de33809b8cf

1 files changed, 25 insertions, 3 deletions

diff --git a/liblog/fake_writer.c b/liblog/fake_writer.c
index dab8bc54e..2350673e1 100644
--- a/liblog/fake_writer.c
+++ b/liblog/fake_writer.c
@@ -46,9 +46,19 @@ static int fakeOpen() {
     int i;
 
     for (i = 0; i < LOG_ID_MAX; i++) {
-        char buf[sizeof("/dev/log_security")];
+        /*
+         * Known maximum size string, plus an 8 character margin to deal with
+         * possible independent changes to android_log_id_to_name().
+         */
+        char buf[sizeof("/dev/log_security") + 8];
+        if (logFds[i] >= 0) {
+            continue;
+        }
         snprintf(buf, sizeof(buf), "/dev/log_%s", android_log_id_to_name(i));
         logFds[i] = fakeLogOpen(buf, O_WRONLY);
+        if (logFds[i] < 0) {
+            fprintf(stderr, "fakeLogOpen(%s, O_WRONLY) failed\n", buf);
+        }
     }
     return 0;
 }
@@ -66,16 +76,28 @@ static int fakeWrite(log_id_t log_id, struct timespec *ts __unused,
                       struct iovec *vec, size_t nr)
 {
     ssize_t ret;
-    int logFd;
+    size_t i;
+    int logFd, len;
 
     if (/*(int)log_id >= 0 &&*/ (int)log_id >= (int)LOG_ID_MAX) {
-        return -EBADF;
+        return -EINVAL;
+    }
+
+    len = 0;
+    for (i = 0; i < nr; ++i) {
+        len += vec[i].iov_len;
+    }
+
+    if (len > LOGGER_ENTRY_MAX_PAYLOAD) {
+        len = LOGGER_ENTRY_MAX_PAYLOAD;
     }
 
     logFd = logFds[(int)log_id];
     ret = TEMP_FAILURE_RETRY(fakeLogWritev(logFd, vec, nr));
     if (ret < 0) {
         ret = -errno;
+    } else if (ret > len) {
+        ret = len;
     }
 
     return ret;