Changed logging functions in bionic/logd_write.c.
Main differences from original code:
1. now log channel for LOG_ID_MAIN may exist even if LOG_ID_RADIO
facility failed.
2. __write_to_log_null() now acts as always successful function.
3. it's more simplier to add new logging channels now
ammended commit fixes my typo on line 130
diff --git a/libc/bionic/logd_write.c b/libc/bionic/logd_write.c
index 211b527..3336428 100644
--- a/libc/bionic/logd_write.c
+++ b/libc/bionic/logd_write.c
@@ -46,62 +46,80 @@
#define LOG_BUF_SIZE 1024
typedef enum {
- LOG_ID_MAIN = 0,
+ LOG_ID_NONE = 0,
+ LOG_ID_MAIN,
LOG_ID_RADIO,
LOG_ID_MAX
} log_id_t;
-static int __write_to_log_init(log_id_t, struct iovec *vec);
-static int (*write_to_log)(log_id_t, struct iovec *vec) = __write_to_log_init;
+/* logger handles writing to object, pointed by log channel id */
+typedef int (*logger_function_t)(log_id_t log_id, struct iovec *vec);
+
+typedef struct {
+ logger_function_t logger;
+ int fd;
+ const char *path;
+} log_channel_t;
+
+static int __write_to_log_init(log_id_t log_id, struct iovec *vec);
+static int __write_to_log_null(log_id_t log_id, struct iovec *vec);
+
static pthread_mutex_t log_init_lock = PTHREAD_MUTEX_INITIALIZER;
-static int log_fds[(int)LOG_ID_MAX] = { -1, -1 };
+log_channel_t log_channels[LOG_ID_MAX] = {
+ { __write_to_log_null, -1, NULL },
+ { __write_to_log_init, -1, "/dev/"LOGGER_LOG_MAIN },
+ { __write_to_log_init, -1, "/dev/"LOGGER_LOG_RADIO }
+};
-static int __write_to_log_null(log_id_t log_fd, struct iovec *vec)
+static int __write_to_log_null(log_id_t log_id, struct iovec *vec)
{
- return -1;
+ /*
+ * ALTERED behaviour from previous version
+ * always returns successful result
+ */
+ int i = 0;
+ size_t res = 0;
+
+ for ( ; i < 3; ++i) {
+ res += vec[i].iov_len;
+ }
+
+ return (int)res;
}
+/*
+ * it's supposed, that log_id contains valid id always.
+ * this check must be performed in higher level functions
+ */
static int __write_to_log_kernel(log_id_t log_id, struct iovec *vec)
{
ssize_t ret;
- int log_fd;
-
- if ((int)log_id >= 0 && (int)log_id < (int)LOG_ID_MAX) {
- log_fd = log_fds[(int)log_id];
- } else {
- return EBADF;
- }
do {
- ret = writev(log_fd, vec, 3);
- } while (ret < 0 && errno == EINTR);
+ ret = writev(log_channels[log_id].fd, vec, 3);
+ } while ((ret < 0) && (errno == EINTR));
return ret;
}
static int __write_to_log_init(log_id_t log_id, struct iovec *vec)
{
- pthread_mutex_lock(&log_init_lock);
+ if ((LOG_ID_NONE < log_id) && (log_id < LOG_ID_MAX)) {
+ pthread_mutex_lock(&log_init_lock);
- if (write_to_log == __write_to_log_init) {
- log_fds[LOG_ID_MAIN] = open("/dev/"LOGGER_LOG_MAIN, O_WRONLY);
- log_fds[LOG_ID_RADIO] = open("/dev/"LOGGER_LOG_RADIO, O_WRONLY);
+ int fd = open(log_channels[log_id].path, O_WRONLY);
- write_to_log = __write_to_log_kernel;
+ log_channels[log_id].logger =
+ (fd < 0) ? __write_to_log_null : __write_to_log_kernel;
- if (log_fds[LOG_ID_MAIN] < 0 || log_fds[LOG_ID_RADIO] < 0) {
- close(log_fds[LOG_ID_MAIN]);
- close(log_fds[LOG_ID_RADIO]);
- log_fds[LOG_ID_MAIN] = -1;
- log_fds[LOG_ID_RADIO] = -1;
- write_to_log = __write_to_log_null;
- }
+ pthread_mutex_unlock(&log_init_lock);
+
+ return log_channels[log_id].logger(log_id, vec);
}
- pthread_mutex_unlock(&log_init_lock);
-
- return write_to_log(log_id, vec);
+ /* log_id is invalid */
+ return -1;
}
static int __android_log_write(int prio, const char *tag, const char *msg)
@@ -109,7 +127,7 @@
struct iovec vec[3];
log_id_t log_id = LOG_ID_MAIN;
- if (!tag)
+ if (tag == NULL)
tag = "";
if (!strcmp(tag, "HTC_RIL"))
@@ -122,7 +140,7 @@
vec[2].iov_base = (void *) msg;
vec[2].iov_len = strlen(msg) + 1;
- return write_to_log(log_id, vec);
+ return log_channels[log_id].logger(log_id, vec);
}
