recovery: turn on text display for install errors in debug builds

Hopefully this will reduce the number of OTA "bugs" reported that are
really just someone having changed their system partition,
invalidating future incremental OTAs.

Also fixes a longstanding TODO about putting LOGE() output in the
on-screen display.

Change-Id: I44e5be65b2dee7ebce2cce28ccd920dc3d6e522e

common.h

@@ -18,13 +18,13 @@
 #define RECOVERY_COMMON_H
 
 #include <stdio.h>
+#include <stdarg.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-// TODO: restore ui_print for LOGE
-#define LOGE(...) fprintf(stdout, "E:" __VA_ARGS__)
+#define LOGE(...) ui_print("E:" __VA_ARGS__)
 #define LOGW(...) fprintf(stdout, "W:" __VA_ARGS__)
 #define LOGI(...) fprintf(stdout, "I:" __VA_ARGS__)
 
@@ -44,6 +44,8 @@ typedef struct fstab_rec Volume;
 // fopen a file, mounting volumes and making parent dirs as necessary.
 FILE* fopen_path(const char *path, const char *mode);
 
+void ui_print(const char* format, ...);
+
 #ifdef __cplusplus
 }
 #endif

recovery.cpp

@@ -15,11 +15,13 @@
  */
 
 #include <ctype.h>
+#include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <getopt.h>
 #include <limits.h>
 #include <linux/input.h>
+#include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -27,7 +29,6 @@
 #include <sys/types.h>
 #include <time.h>
 #include <unistd.h>
-#include <dirent.h>
 
 #include "bootloader.h"
 #include "common.h"
@@ -801,6 +802,24 @@ load_locale_from_cache() {
     }
 }
 
+static RecoveryUI* gCurrentUI = NULL;
+
+void
+ui_print(const char* format, ...) {
+    char buffer[256];
+
+    va_list ap;
+    va_start(ap, format);
+    vsnprintf(buffer, sizeof(buffer), format, ap);
+    va_end(ap);
+
+    if (gCurrentUI != NULL) {
+        gCurrentUI->Print("%s", buffer);
+    } else {
+        fputs(buffer, stdout);
+    }
+}
+
 int
 main(int argc, char **argv) {
     time_t start = time(NULL);
@@ -856,6 +875,7 @@ main(int argc, char **argv) {
 
     Device* device = make_device();
     ui = device->GetUI();
+    gCurrentUI = ui;
 
     ui->Init();
     ui->SetLocale(locale);
@@ -909,7 +929,18 @@ main(int argc, char **argv) {
                 LOGE("Cache wipe (requested by package) failed.");
             }
         }
-        if (status != INSTALL_SUCCESS) ui->Print("Installation aborted.\n");
+        if (status != INSTALL_SUCCESS) {
+            ui->Print("Installation aborted.\n");
+
+            // If this is an eng or userdebug build, then automatically
+            // turn the text display on if the script fails so the error
+            // message is visible.
+            char buffer[PROPERTY_VALUE_MAX+1];
+            property_get("ro.build.fingerprint", buffer, "");
+            if (strstr(buffer, ":userdebug/") || strstr(buffer, ":eng/")) {
+                ui->ShowText(true);
+            }
+        }
     } else if (wipe_data) {
         if (device->WipeData()) status = INSTALL_ERROR;
         if (erase_volume("/data")) status = INSTALL_ERROR;

verifier_test.cpp

@@ -18,6 +18,7 @@
 #include <stdlib.h>
 #include <stdarg.h>
 
+#include "common.h"
 #include "verifier.h"
 #include "ui.h"
 #include "mincrypt/sha.h"
@@ -115,13 +116,10 @@ class FakeUI : public RecoveryUI {
     bool IsTextVisible() { return false; }
     bool WasTextEverVisible() { return false; }
     void Print(const char* fmt, ...) {
-        char buf[256];
         va_list ap;
         va_start(ap, fmt);
-        vsnprintf(buf, 256, fmt, ap);
+        vfprintf(stderr, fmt, ap);
         va_end(ap);
-
-        fputs(buf, stderr);
     }
 
     void StartMenu(const char* const * headers, const char* const * items,
@@ -130,6 +128,14 @@ class FakeUI : public RecoveryUI {
     void EndMenu() { }
 };
 
+void
+ui_print(const char* format, ...) {
+    va_list ap;
+    va_start(ap, format);
+    vfprintf(stdout, format, ap);
+    va_end(ap);
+}
+
 int main(int argc, char **argv) {
     if (argc < 2 || argc > 4) {
         fprintf(stderr, "Usage: %s [-sha256] [-f4 | -file <keys>] <package>\n", argv[0]);