Log update outputs in order

Although stdout and stderr are both redirected to log file with no
buffering, we are seeing some outputs are mixed in random order.
This is because ui_print commands from the updater are passed to the
recovery binary via a pipe, which may interleave with other outputs
that go to stderr directly.

In recovery, adding ui::PrintOnScreenOnly() function to handle
ui_print command, which skips printing to stdout. Meanwhile, updater
prints the contents to stderr in addition to piping them to recovery.

Change-Id: Idda93ea940d2e23a0276bb8ead4aa70a3cb97700

1 files changed, 25 insertions, 10 deletions

diff --git a/screen_ui.cpp b/screen_ui.cpp
index ff95915..ddf85c1 100644
--- a/screen_ui.cpp
+++ b/screen_ui.cpp
@@ -30,8 +30,10 @@
 
 #include <vector>
 
-#include "base/strings.h"
-#include "cutils/properties.h"
+#include <base/strings.h>
+#include <base/stringprintf.h>
+#include <cutils/properties.h>
+
 #include "common.h"
 #include "device.h"
 #include "minui/minui.h"
@@ -506,18 +508,17 @@ void ScreenRecoveryUI::SetStage(int current, int max) {
     pthread_mutex_unlock(&updateMutex);
 }
 
-void ScreenRecoveryUI::Print(const char *fmt, ...) {
-    char buf[256];
-    va_list ap;
-    va_start(ap, fmt);
-    vsnprintf(buf, 256, fmt, ap);
-    va_end(ap);
+void ScreenRecoveryUI::PrintV(const char* fmt, bool copy_to_stdout, va_list ap) {
+    std::string str;
+    android::base::StringAppendV(&str, fmt, ap);
 
-    fputs(buf, stdout);
+    if (copy_to_stdout) {
+        fputs(str.c_str(), stdout);
+    }
 
     pthread_mutex_lock(&updateMutex);
     if (text_rows_ > 0 && text_cols_ > 0) {
-        for (const char* ptr = buf; *ptr != '\0'; ++ptr) {
+        for (const char* ptr = str.c_str(); *ptr != '\0'; ++ptr) {
             if (*ptr == '\n' || text_col_ >= text_cols_) {
                 text_[text_row_][text_col_] = '\0';
                 text_col_ = 0;
@@ -532,6 +533,20 @@ void ScreenRecoveryUI::Print(const char *fmt, ...) {
     pthread_mutex_unlock(&updateMutex);
 }
 
+void ScreenRecoveryUI::Print(const char* fmt, ...) {
+    va_list ap;
+    va_start(ap, fmt);
+    PrintV(fmt, true, ap);
+    va_end(ap);
+}
+
+void ScreenRecoveryUI::PrintOnScreenOnly(const char *fmt, ...) {
+    va_list ap;
+    va_start(ap, fmt);
+    PrintV(fmt, false, ap);
+    va_end(ap);
+}
+
 void ScreenRecoveryUI::PutChar(char ch) {
     pthread_mutex_lock(&updateMutex);
     if (ch != '\n') text_[text_row_][text_col_++] = ch;