Preprocessor mode fixes (#176)

5 files changed, 35 insertions, 33 deletions

diff --git a/nimterop/build.nim b/nimterop/build.nim
index c65ec2a..cc6dc22 100644
--- a/nimterop/build.nim
+++ b/nimterop/build.nim
@@ -620,6 +620,21 @@ proc make*(path, check: string, flags = "", regex = false) =
 
   doAssert findFile(check, path, regex = regex).len != 0, "# make failed"
 
+proc getCompilerMode*(path: string): string =
+  ## Determines a target language mode from an input filename, if one is not already specified.
+  let file = path.splitFile()
+  if file.ext in [".hxx", ".hpp", ".hh", ".H", ".h++", ".cpp", ".cxx", ".cc", ".C", ".c++"]:
+    result = "cpp"
+  elif file.ext in [".h", ".c"]:
+    result = "c"
+
+proc getGccModeArg*(mode: string): string =
+  ## Produces a GCC argument that explicitly sets the language mode to be used by the compiler.
+  if mode == "cpp":
+    result = "-xc++"
+  elif mode == "c":
+    result = "-xc"
+
 proc getCompiler*(): string =
   var
     compiler =
@@ -632,13 +647,12 @@ proc getCompiler*(): string =
 
   result = getEnv("CC", compiler)
 
-proc getGccPaths*(mode = "c"): seq[string] =
+proc getGccPaths*(mode: string): seq[string] =
   var
     nul = when defined(Windows): "nul" else: "/dev/null"
-    mmode = if mode == "cpp": "c++" else: mode
     inc = false
 
-    (outp, _) = execAction(&"""{getCompiler()} -Wp,-v -x{mmode} {nul}""", die = false)
+    (outp, _) = execAction(&"""{getCompiler()} -Wp,-v {getGccModeArg(mode)} {nul}""", die = false)
 
   for line in outp.splitLines():
     if "#include <...> search starts here" in line:
@@ -655,13 +669,12 @@ proc getGccPaths*(mode = "c"): seq[string] =
   when defined(osx):
     result.add(execAction("xcrun --show-sdk-path").output.strip() & "/usr/include")
 
-proc getGccLibPaths*(mode = "c"): seq[string] =
+proc getGccLibPaths*(mode: string): seq[string] =
   var
     nul = when defined(Windows): "nul" else: "/dev/null"
-    mmode = if mode == "cpp": "c++" else: mode
     linker = when defined(OSX): "-Xlinker" else: ""
 
-    (outp, _) = execAction(&"""{getCompiler()} {linker} -v -x{mmode} {nul}""", die = false)
+    (outp, _) = execAction(&"""{getCompiler()} {linker} -v {getGccModeArg(mode)} {nul}""", die = false)
 
   for line in outp.splitLines():
     if "LIBRARY_PATH=" in line:
@@ -680,14 +693,14 @@ proc getGccLibPaths*(mode = "c"): seq[string] =
   when defined(osx):
     result.add "/usr/lib"
 
-proc getStdPath(header: string): string =
-  for inc in getGccPaths():
+proc getStdPath(header, mode: string): string =
+  for inc in getGccPaths(mode):
     result = findFile(header, inc, recurse = false, first = true)
     if result.len != 0:
       break
 
-proc getStdLibPath(lname: string): string =
-  for lib in getGccLibPaths():
+proc getStdLibPath(lname, mode: string): string =
+  for lib in getGccLibPaths(mode):
     result = findFile(lname, lib, recurse = false, first = true, regex = true)
     if result.len != 0:
       break
@@ -973,6 +986,7 @@ macro getHeader*(header: static[string], giturl: static[string] = "", dlurl: sta
         gDefines[verStr]
       else:
         ""
+    mode = getCompilerMode(header)
 
   # Use alternate library names if specified for regex search
   if altNames.len != 0:
@@ -1008,9 +1022,9 @@ macro getHeader*(header: static[string], giturl: static[string] = "", dlurl: sta
 
       # Look in standard path if requested by user
       stdPath =
-        when `nameStd`: getStdPath(`header`) else: ""
+        when `nameStd`: getStdPath(`header`, `mode`) else: ""
       stdLPath =
-        when `nameStd`: getStdLibPath(`lname`) else: ""
+        when `nameStd`: getStdLibPath(`lname`, `mode`) else: ""
 
       # Look elsewhere if requested while prioritizing standard paths
       prePath =
diff --git a/nimterop/getters.nim b/nimterop/getters.nim
index 044cde7..986c54d 100644
--- a/nimterop/getters.nim
+++ b/nimterop/getters.nim
@@ -495,11 +495,10 @@ proc removeStatic(content: string): string =
       result.add(body.replace(re"(?m)^(.*\n?)", "//$1"))
   )
 
-proc getPreprocessor*(gState: State, fullpath: string, mode = "cpp"): string =
+proc getPreprocessor*(gState: State, fullpath: string): string =
   var
-    mmode = if mode == "cpp": "c++" else: mode
     cmts = if gState.nocomments: "" else: "-CC"
-    cmd = &"""{getCompiler()} -E {cmts} -dD -x{mmode} -w """
+    cmd = &"""{getCompiler()} -E {cmts} -dD {getGccModeArg(gState.mode)} -w """
 
     rdata: seq[string] = @[]
     start = false
diff --git a/nimterop/globals.nim b/nimterop/globals.nim
index 701db61..42f7cb7 100644
--- a/nimterop/globals.nim
+++ b/nimterop/globals.nim
@@ -98,9 +98,6 @@ type
 
     nodeBranch*: seq[string]
 
-  CompileMode = enum
-    c, cpp
-
   Feature* = enum
     ast2
 
@@ -113,11 +110,9 @@ template nBl(s: typed): untyped {.used.} =
 template Bl(s: typed): untyped {.used.} =
   (s.len == 0)
 
-const modeDefault {.used.} = $cpp
-
 when not declared(CIMPORT):
   export gAtoms, gExpressions, gEnumVals, Kind, Ast, AstTable, State, NimState,
-    nBl, Bl, CompileMode, modeDefault
+    nBl, Bl
 
   # Redirect output to file when required
   template gecho*(args: string) {.dirty.} =
@@ -133,4 +128,4 @@ when not declared(CIMPORT):
 
   template decho*(str: untyped): untyped =
     if nimState.gState.debug:
-      necho str.getCommented()
\ No newline at end of file
+      necho str.getCommented()
diff --git a/nimterop/toast.nim b/nimterop/toast.nim
index fe63fb9..c3d6a3d 100644
--- a/nimterop/toast.nim
+++ b/nimterop/toast.nim
@@ -2,23 +2,18 @@ import os, osproc, strformat, strutils, times
 
 import "."/treesitter/[api, c, cpp]
 
-import "."/[ast, ast2, globals, getters, grammar]
+import "."/[ast, ast2, globals, getters, grammar, build]
 
 proc process(gState: State, path: string, astTable: AstTable) =
   doAssert existsFile(path), &"Invalid path {path}"
 
-  var
-    parser = tsParserNew()
-    ext = path.splitFile().ext
+  var parser = tsParserNew()
 
   defer:
     parser.tsParserDelete()
 
   if gState.mode.Bl:
-    if ext in [".h", ".c"]:
-      gState.mode = "c"
-    elif ext in [".hxx", ".hpp", ".hh", ".H", ".h++", ".cpp", ".cxx", ".cc", ".C", ".c++"]:
-      gState.mode = "cpp"
+    gState.mode = getCompilerMode(path)
 
   if gState.preprocess:
     gState.code = gState.getPreprocessor(path)
@@ -61,7 +56,7 @@ proc main(
     feature: seq[Feature] = @[],
     includeHeader = false,
     includeDirs: seq[string] = @[],
-    mode = modeDefault,
+    mode = "",
     nim: string = "nim",
     nocomments = false,
     output = "",
diff --git a/tests/tpcre.nim b/tests/tpcre.nim
index f896e9c..c8e8059 100644
--- a/tests/tpcre.nim
+++ b/tests/tpcre.nim
@@ -31,8 +31,7 @@ cPlugin:
     sym.name = sym.name.replace("pcre_", "")
 
 const FLAGS {.strdefine.} = ""
-cImport(pcreH, dynlib="dynpcre", flags = FLAGS)
-
+cImport(pcreH, dynlib="dynpcre", flags="--mode=c " & FLAGS)
 echo version()
 
 when FLAGS.len != 0: