Convert relative installation directory path to absolute in build scripts

4 files changed, 35 insertions, 1 deletions

diff --git a/build-clang.bat b/build-clang.bat
index f8b8f31..16cdae0 100644
--- a/build-clang.bat
+++ b/build-clang.bat
@@ -152,6 +152,10 @@ if "_%1_" == "__" (
   set "cxx=%1"
 )
 
+rem Convert a relative path to an absolute.
+rem
+for /F "delims=|" %%D in ("%idir%") do set "idir=%%~dpnxD"
+
 rem Certificate to trust.
 rem
 if not "_%trust%_" == "__" (
diff --git a/build-mingw.bat b/build-mingw.bat
index 7e62685..21704b4 100644
--- a/build-mingw.bat
+++ b/build-mingw.bat
@@ -161,6 +161,10 @@ if not "_%3_" == "__" (
   set "trust=%3"
 )
 
+rem Convert a relative path to an absolute.
+rem
+for /F "delims=|" %%D in ("%idir%") do set "idir=%%~dpnxD"
+
 rem Certificate to trust.
 rem
 if not "_%trust%_" == "__" (
diff --git a/build-msvc.bat b/build-msvc.bat
index 2f0ed6b..e9416a3 100644
--- a/build-msvc.bat
+++ b/build-msvc.bat
@@ -8,7 +8,8 @@ goto start
 
 :usage
 echo.
-echo Usage: %0 [/?] [^<options^>] [^<cl-compiler^>]
+rem echo Usage: %0 [/?] [^<options^>] [^<cl-compiler^>]
+echo Usage: %0 [/?] [^<options^>]
 echo Options:
 echo   --local              Don't build from packages, only from local source.
 echo   --install-dir ^<dir^>  Alternative installation directory.
@@ -140,6 +141,10 @@ rem ) else (
 rem  set "cxx=%1"
 rem )
 
+rem Convert a relative path to an absolute.
+rem
+for /F "delims=|" %%D in ("%idir%") do set "idir=%%~dpnxD"
+
 rem Certificate to trust.
 rem
 if not "_%trust%_" == "__" (
diff --git a/build.sh b/build.sh
index 9d83209..a1ba1cf 100755
--- a/build.sh
+++ b/build.sh
@@ -225,6 +225,12 @@ if test -n "$make"; then
   fi
 fi
 
+# If the installation directory is unspecified, then assume it is /usr/local.
+# Otherwise, if it is a relative path, then convert it to an absolute path,
+# unless the realpath program is not present on the system or doesn't
+# recognize any of the options we pass, in which case fail, advising to
+# specify an absolute installation directory.
+#
 if test -z "$idir"; then
   idir=/usr/local
   private=config.install.private=build2
@@ -235,6 +241,21 @@ if test -z "$idir"; then
   if test -z "$sudo"; then
     sudo="sudo"
   fi
+elif test -n "$(echo "$idir" | sed -n 's#^[^/].*$#true#p')"; then
+
+  if ! command -v realpath >/dev/null 2>&1; then
+    diag "error: unable to execute realpath: command not found"
+    diag "  info: specify absolute installation directory path"
+    exit 1
+  fi
+
+  # Don't resolve symlinks and allow non-existent path components.
+  #
+  if ! idir="$(realpath -s -m "$idir" 2>/dev/null)"; then
+    diag "error: realpath does not recognize -s -m"
+    diag "  info: specify absolute installation directory path"
+    exit 1
+  fi
 fi
 
 if test "$sudo" = false; then