For some reason, ofstream fails to write to sysfs nodes on Android. So use old-fashion open()/write()/close(). Signed-off-by: Daniel Leung <daniel.leung(a)linux.intel.com&gt; --- .../0001-Android-disable-C-exceptions.patch | 34 +++++----------------- src/lib.cpp | 14 +++++++++ 2 files changed, 22 insertions(+), 26 deletions(-) diff --git a/patches/Android/0001-Android-disable-C-exceptions.patch b/patches/Android/0001-Android-disable-C-exceptions.patch index 435cd95..b11bdc7 100644 --- a/patches/Android/0001-Android-disable-C-exceptions.patch +++ b/patches/Android/0001-Android-disable-C-exceptions.patch @@ -1,4 +1,4 @@ -From 604d8f6da54524f0f7bfdd7aea91d353b4f1b612 Mon Sep 17 00:00:00 2001 +From 4570b7d6559047b384c50b4766e168fd5e11db8e Mon Sep 17 00:00:00 2001 From: Daniel Leung <daniel.leung(a)intel.com&gt; Date: Wed, 25 Feb 2015 13:24:14 -0800 Subject: [PATCH 1/1] Android: disable C++ exceptions @@ -11,11 +11,11 @@ Signed-off-by: Daniel Leung <daniel.leung(a)intel.com&gt; Android.mk | 2 +- src/devices/ahci.cpp | 8 ++++++++ src/devices/alsa.cpp | 8 ++++++++ - src/lib.cpp | 19 +++++++++++++++++++ - 4 files changed, 36 insertions(+), 1 deletion(-) + src/lib.cpp | 15 +++++++++++++++ + 4 files changed, 32 insertions(+), 1 deletion(-) diff --git a/Android.mk b/Android.mk -index dd98d0f..f6b8689 100644 +index 0c95e3a..ff1040a 100644 --- a/Android.mk +++ b/Android.mk @@ -14,7 +14,7 @@ LOCAL_MODULE := powertop @@ -128,28 +128,10 @@ index a1fca71..ba3c0b6 100644 p = (end_active - start_active) / (0.001 + end_active + end_inactive - start_active - start_inactive) * 100.0; report_utilization(name, p); diff --git a/src/lib.cpp b/src/lib.cpp -index 0dec0b7..91dac7a 100644 +index 24d6d07..4812ff1 100644 --- a/src/lib.cpp +++ b/src/lib.cpp -@@ -176,13 +176,17 @@ void write_sysfs(const string &filename, const string &value) - file.open(filename.c_str(), ios::out); - if (!file) - return; -+#ifndef DISABLE_TRYCATCH - try - { -+#endif - file << value; - file.close(); -+#ifndef DISABLE_TRYCATCH - } catch (std::exception &exc) { - return; - } -+#endif - } - - int read_sysfs(const string &filename, bool *ok) -@@ -196,16 +200,23 @@ int read_sysfs(const string &filename, bool *ok) +@@ -210,16 +210,23 @@ int read_sysfs(const string &filename, bool *ok) *ok = false; return 0; } @@ -173,7 +155,7 @@ index 0dec0b7..91dac7a 100644 file.close(); return i; } -@@ -219,17 +230,21 @@ string read_sysfs_string(const string &filename) +@@ -233,17 +240,21 @@ string read_sysfs_string(const string &filename) file.open(filename.c_str(), ios::in); if (!file) return ""; @@ -195,7 +177,7 @@ index 0dec0b7..91dac7a 100644 return content; } -@@ -246,17 +261,21 @@ string read_sysfs_string(const char *format, const char *param) +@@ -260,17 +271,21 @@ string read_sysfs_string(const char *format, const char *param) file.open(filename, ios::in); if (!file) return ""; diff --git a/src/lib.cpp b/src/lib.cpp index 6b1bc0a..24d6d07 100644 --- a/src/lib.cpp +++ b/src/lib.cpp @@ -171,6 +171,7 @@ void set_max_cpu(int cpu) void write_sysfs(const string &filename, const string &value) { +#ifndef ANDROID ofstream file; file.open(filename.c_str(), ios::out); @@ -183,6 +184,19 @@ void write_sysfs(const string &filename, const string &value) } catch (std::exception &exc) { return; } +#else + int fd; + + fd = ::open(filename.c_str(), O_WRONLY); + if (fd < 0) + return; + + ::write(fd, value.c_str(), value.length()); + + close(fd); + + return; +#endif } int read_sysfs(const string &filename, bool *ok) -- 1.8.3.2