Consolidate build system usage documentation into source control

Bug: 62201421

Test: make help
Change-Id: I7a7c917f767590657761396dd0545224ff98f27b

1 files changed, 53 insertions, 0 deletions

diff --git a/help.sh b/help.sh
new file mode 100755
index 0000000000..c031dcc7ed
--- /dev/null
+++ b/help.sh
@@ -0,0 +1,53 @@
+#!/bin/bash
+
+# locate some directories
+cd "$(dirname $0)"
+SCRIPT_DIR="${PWD}"
+cd ../..
+TOP="${PWD}"
+
+message='The basic Android build process is:
+
+cd '"${TOP}"'
+source build/envsetup.sh    # Add "lunch" (and other utilities and variables)
+                            # to the shell environment.
+lunch [<product>-<variant>] # Choose the device to target.
+m -j [<goals>]              # Execute the configured build.
+
+Usage of "m" imitates usage of the program "make".
+See '"${SCRIPT_DIR}"'/README.txt for more info about build usage and concepts.
+
+Common goals are:
+
+    clean                   (aka clobber) equivalent to rm -rf out/
+    checkbuild              Build every module defined in the source tree
+    droid                   Default target
+    nothing                 Do not build anything, just parse and validate the build structure
+
+    java                    Build all the java code in the source tree
+    native                  Build all the native code in the source tree
+
+    host                    Build all the host code (not to be run on a device) in the source tree
+    target                  Build all the target code (to be run on the device) in the source tree
+
+    (java|native)-(host|target)
+    (host|target)-(java|native)
+                            Build the intersection of the two given arguments
+
+    snod                    Quickly rebuild the system image from built packages
+                            Stands for "System, NO Dependencies"
+    vnod                    Quickly rebuild the vendor image from built packages
+                            Stands for "Vendor, NO Dependencies"
+
+
+So, for example, you could run:
+
+cd '"${TOP}"'
+source build/envsetup.sh
+lunch aosp_arm-userdebug
+m -j java
+
+to build all of the java code for the userdebug variant of the aosp_arm device.
+'
+
+echo "$message"