lib: Add path_expandvars() internal API call

3 files changed, 48 insertions, 0 deletions

diff --git a/host/lib/utils/CMakeLists.txt b/host/lib/utils/CMakeLists.txt
index 7af094e83..62d1ba090 100644
--- a/host/lib/utils/CMakeLists.txt
+++ b/host/lib/utils/CMakeLists.txt
@@ -168,6 +168,7 @@ LIBUHD_APPEND_SOURCES(
     ${CMAKE_CURRENT_SOURCE_DIR}/load_modules.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/log.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/paths.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/pathslib.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/platform.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/static.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/tasks.cpp
diff --git a/host/lib/utils/paths.cpp b/host/lib/utils/paths.cpp
index d609e254f..8a7ba001f 100644
--- a/host/lib/utils/paths.cpp
+++ b/host/lib/utils/paths.cpp
@@ -8,6 +8,7 @@
 #include <uhd/config.hpp>
 #include <uhd/exception.hpp>
 #include <uhd/utils/paths.hpp>
+#include <uhdlib/utils/paths.hpp>
 
 #include <boost/algorithm/string.hpp>
 #include <boost/bind.hpp>
@@ -96,6 +97,7 @@ static std::vector<std::string> get_env_paths(const std::string &var_name){
 }
 
 #ifndef UHD_PLATFORM_WIN32
+// NOTE: This could be replaced by path_expandvars()
 /*! Expand a tilde character to the $HOME path.
  *
  * The path passed to this function must start with the tilde character in order
diff --git a/host/lib/utils/pathslib.cpp b/host/lib/utils/pathslib.cpp
new file mode 100644
index 000000000..cbb0d0917
--- /dev/null
+++ b/host/lib/utils/pathslib.cpp
@@ -0,0 +1,45 @@
+//
+// Copyright 2018 Ettus Research, a National Instruments Company
+//
+// SPDX-License-Identifier: GPL-3.0+
+//
+
+#include <uhd/config.hpp>
+#include <uhdlib/utils/paths.hpp>
+
+#ifdef BOOST_MSVC
+#  include <windows.h>
+#else
+#  include <wordexp.h>
+#endif
+
+std::string uhd::path_expandvars(const std::string& path)
+{
+    if (path.empty()) {
+        return path;
+    }
+#ifdef BOOST_MSVC
+    constexpr size_t max_pathlen = 4096;
+    char result[max_pathlen];
+    const size_t result_len = ExpandEnvironmentStrings(
+        path.c_str(),
+        &result[0],
+        max_pathlen
+    );
+    if (result == 0) {
+        return path;
+    }
+    return std::string(result, result+result_len);
+#else
+    wordexp_t p;
+    std::string return_value;
+    if (wordexp(path.c_str(), &p, 0) == 0 && p.we_wordc > 0) {
+        return_value = std::string(p.we_wordv[0]);
+    } else {
+        return_value = path;
+    }
+    wordfree(&p);
+    return return_value;
+#endif
+}
+