Android Support

Adding instruction on how to build for Android on README. Included
Android patches to build PowerTOP.

Signed-off-by: Alexandra Yates <alexandra.yates@linux.intel.com>

README

@@ -25,6 +25,33 @@ ncurses-devel  (required)
 libnl-devel    (required)
 kernel version => 2.6.38
 
+
+Build PowerTop for Android LollyPop
+------------------------------------
+
+1. Obtain pciutils and ncurses libraries.
+   Skip this step if they are already in the tree.
+
+   pciutils: Clone
+       https://github.com/trevd/android_external_pciutils
+   into external/pciutils
+
+   ncurses: Clone
+       https://github.com/cvpcs/android_external_libncurses
+   into external/ncurses
+
+2. Run
+       ./src/csstoh.sh src/powertop.css src/css.h
+   to generate the css.h header file.
+
+3. Apply patches inside patches/Android
+
+4. PowerTop can be built with top level make,
+   or by doing "mm".
+
+   The resulting binary is under $ANDROID_PRODUCT_OUT/system/bin/powertop
+
+
 Kernel Parameters:
 ------------------
 

patches/android/disable-C-exceptions.patch

@@ -0,0 +1,122 @@
+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@linux.intel.com>
+---
+ .../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@intel.com>
+ 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@intel.com>
+  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
+
+_______________________________________________
+PowerTop mailing list
+PowerTop@lists.01.org
+https://lists.01.org/mailman/listinfo/powertop

patches/android/prevent_segfaults.patch

@@ -0,0 +1,39 @@
+The mbsrtowcs() in Android seems to change the content of
+source pointer to 0x00. So save a copy of the source
+string so we can manipulate it later, preventing segfaults.
+
+Signed-off-by: Daniel Leung <daniel.leung@linux.intel.com>
+---
+ src/lib.cpp | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/src/lib.cpp b/src/lib.cpp
+index 0dec0b7..6b1bc0a 100644
+--- a/src/lib.cpp
++++ b/src/lib.cpp
+@@ -263,6 +263,7 @@ string read_sysfs_string(const char *format, const char *param)
+ void align_string(char *buffer, size_t min_sz, size_t max_sz)
+ {
+ 	size_t sz;
++	char *buf = buffer;
+
+ 	/** mbsrtowcs() allows NULL dst and zero sz,
+ 	 * comparing to mbstowcs(), which causes undefined
+@@ -275,8 +276,9 @@ void align_string(char *buffer, size_t min_sz, size_t max_sz)
+ 		buffer[min_sz] = 0x00;
+ 		return;
+ 	}
++
+ 	while (sz < min_sz) {
+-		strcat(buffer, " ");
++		strcat(buf, " ");
+ 		sz++;
+ 	}
+ }
+-- 
+1.8.3.2
+
+_______________________________________________
+PowerTop mailing list
+PowerTop@lists.01.org
+https://lists.01.org/mailman/listinfo/powertop