Replace _exit(-1) with _exit(EXIT_FAILURE).

-1 is not a valid exit status.

Also replace a few exit(1) with exit(EXIT_FAILURE).

Test: mmma bootable/recovery
Change-Id: I4596c8328b770bf95acccc06a4401bd5cabd4bfd
diff --git a/adb_install.cpp b/adb_install.cpp
index fab72f8..79b8df9 100644
--- a/adb_install.cpp
+++ b/adb_install.cpp
@@ -78,7 +78,7 @@
     pid_t child;
     if ((child = fork()) == 0) {
         execl("/sbin/recovery", "recovery", "--adbd", NULL);
-        _exit(-1);
+        _exit(EXIT_FAILURE);
     }
 
     // FUSE_SIDELOAD_HOST_PATHNAME will start to exist once the host
diff --git a/install.cpp b/install.cpp
index 91e4875..ce89e0d 100644
--- a/install.cpp
+++ b/install.cpp
@@ -387,7 +387,7 @@
     // the child process to hang. This deadlock results from an improperly
     // copied mutex in the ui functions.
     fprintf(stdout, "E:Can't run %s (%s)\n", chr_args[0], strerror(errno));
-    _exit(-1);
+    _exit(EXIT_FAILURE);
   }
   close(pipefd[1]);
 
diff --git a/recovery.cpp b/recovery.cpp
index 25d3546..29d7ab8 100644
--- a/recovery.cpp
+++ b/recovery.cpp
@@ -243,7 +243,7 @@
         if (log_fp == nullptr) {
             PLOG(ERROR) << "fopen \"" << filename << "\" failed";
             close(pipefd[0]);
-            _exit(1);
+            _exit(EXIT_FAILURE);
         }
 
         FILE* pipe_fp = fdopen(pipefd[0], "r");
@@ -251,7 +251,7 @@
             PLOG(ERROR) << "fdopen failed";
             check_and_fclose(log_fp, filename);
             close(pipefd[0]);
-            _exit(1);
+            _exit(EXIT_FAILURE);
         }
 
         char* line = nullptr;
@@ -273,7 +273,7 @@
         free(line);
         check_and_fclose(log_fp, filename);
         close(pipefd[0]);
-        _exit(1);
+        _exit(EXIT_FAILURE);
     } else {
         // Redirect stdout/stderr to the logger process.
         // Close the unused read end.
diff --git a/roots.cpp b/roots.cpp
index 376fcbd..4a0a494 100644
--- a/roots.cpp
+++ b/roots.cpp
@@ -163,7 +163,7 @@
     pid_t child;
     if ((child = vfork()) == 0) {
         execv(path, argv);
-        _exit(-1);
+        _exit(EXIT_FAILURE);
     }
     waitpid(child, &status, 0);
     if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
diff --git a/updater/blockimg.cpp b/updater/blockimg.cpp
index 6755d78..03ce413 100644
--- a/updater/blockimg.cpp
+++ b/updater/blockimg.cpp
@@ -120,7 +120,7 @@
 
 err:
   LOG(ERROR) << "failed to parse range '" << range_text << "'";
-  exit(1);
+  exit(EXIT_FAILURE);
 }
 
 static bool range_overlaps(const RangeSet& r1, const RangeSet& r2) {
diff --git a/updater/install.cpp b/updater/install.cpp
index 7a8e92f..c7ecdb5 100644
--- a/updater/install.cpp
+++ b/updater/install.cpp
@@ -247,7 +247,7 @@
   pid_t child;
   if ((child = vfork()) == 0) {
     execv(path, argv);
-    _exit(-1);
+    _exit(EXIT_FAILURE);
   }
 
   int status;
@@ -1072,7 +1072,7 @@
   if (child == 0) {
     execv(args2[0], args2);
     PLOG(ERROR) << "run_program: execv failed";
-    _exit(1);
+    _exit(EXIT_FAILURE);
   }
 
   int status;