version: add optional oem version tag (ext/oem-<version>) and log it

src/lib/version/px_update_git_header.py

@@ -84,15 +84,26 @@ except:
     git_branch_name = ''
 git_version_short = git_version[0:16]
 
+# OEM version
+try:
+    oem_tag = subprocess.check_output('git describe --match ext/oem-* --tags'.split(),
+                                      stderr=subprocess.STDOUT).decode('utf-8').strip()
+    oem_tag = oem_tag[8:]
+except:
+    oem_tag = ''
+
 header += """
 #define PX4_GIT_VERSION_STR  "{git_version}"
 #define PX4_GIT_VERSION_BINARY 0x{git_version_short}
 #define PX4_GIT_TAG_STR  "{git_tag}"
 #define PX4_GIT_BRANCH_NAME  "{git_branch_name}"
+
+#define PX4_GIT_OEM_VERSION_STR  "{oem_tag}"
 """.format(git_tag=git_tag,
            git_version=git_version,
            git_version_short=git_version_short,
-           git_branch_name=git_branch_name)
+           git_branch_name=git_branch_name,
+           oem_tag=oem_tag)
 
 
 # ECL

src/lib/version/version.c

@@ -370,3 +370,8 @@ uint64_t px4_os_version_binary(void)
 #endif
 }
 
+const char *px4_firmware_oem_version_string(void)
+{
+	return PX4_GIT_OEM_VERSION_STR;
+}
+

src/lib/version/version.h

@@ -187,5 +187,10 @@ __EXPORT uint64_t px4_mavlink_lib_version_binary(void);
  */
 __EXPORT uint64_t px4_os_version_binary(void);
 
+/**
+ * get the git oem version tag (can be empty, no particular format)
+ */
+__EXPORT const char *px4_firmware_oem_version_string(void);
+
 __END_DECLS