C2nim, cmake and make support, additional documentation

2 files changed, 178 insertions, 13 deletions

diff --git a/nimterop/cimport.nim b/nimterop/cimport.nim
index 5717ac3..a4e1761 100644
--- a/nimterop/cimport.nim
+++ b/nimterop/cimport.nim
@@ -124,7 +124,7 @@ proc getNimCheckError(output: string): tuple[tmpFile, errors: string] =
 
   result.errors = "\n\n" & check
 
-proc getToast(fullpath: string, recurse: bool = false, dynlib: string = ""): string =
+proc getToast(fullpath: string, recurse: bool = false, dynlib: string = "", noNimout = false): string =
   var
     ret = 0
     cmd = when defined(Windows): "cmd /c " else: ""
@@ -132,7 +132,7 @@ proc getToast(fullpath: string, recurse: bool = false, dynlib: string = ""): str
   let toastExe = toastExePath()
   doAssert fileExists(toastExe), "toast not compiled: " & toastExe.quoteShell &
     " make sure 'nimble build' or 'nimble install' built it"
-  cmd &= &"{toastExe} --pnim --preprocess"
+  cmd &= &"{toastExe} --preprocess"
 
   if recurse:
     cmd.add " --recurse"
@@ -143,17 +143,20 @@ proc getToast(fullpath: string, recurse: bool = false, dynlib: string = ""): str
   for i in gStateCT.includeDirs:
     cmd.add &" --includeDirs+={i.quoteShell}"
 
-  if dynlib.len != 0:
-    cmd.add &" --dynlib={dynlib}"
+  if not noNimout:
+    cmd.add &" --pnim"
+
+    if dynlib.len != 0:
+      cmd.add &" --dynlib={dynlib}"
 
-  if gStateCT.symOverride.len != 0:
-    cmd.add &" --symOverride={gStateCT.symOverride.join(\",\")}"
+    if gStateCT.symOverride.len != 0:
+      cmd.add &" --symOverride={gStateCT.symOverride.join(\",\")}"
 
-  when (NimMajor, NimMinor, NimPatch) >= (0, 19, 9):
-    cmd.add &" --nim:{getCurrentCompilerExe().quoteShell}"
+    when (NimMajor, NimMinor, NimPatch) >= (0, 19, 9):
+      cmd.add &" --nim:{getCurrentCompilerExe().quoteShell}"
 
-  if gStateCT.pluginSourcePath.nBl:
-    cmd.add &" --pluginSourcePath={gStateCT.pluginSourcePath.quoteShell}"
+    if gStateCT.pluginSourcePath.nBl:
+      cmd.add &" --pluginSourcePath={gStateCT.pluginSourcePath.quoteShell}"
 
   cmd.add &" {fullpath.quoteShell}"
 
@@ -542,3 +545,78 @@ macro cImport*(filename: static string, recurse: static bool = false, dynlib: st
       (tmpFile, errors) = getNimCheckError(output)
     doAssert false, errors & "\n\nNimterop codegen limitation or error - review 'nim check' output above generated for " & tmpFile
 
+macro c2nImport*(filename: static string, recurse: static bool = false, dynlib: static string = "",
+  mode: static string = "c", flags: static string = ""): untyped =
+  ## Import all supported definitions from specified header file using ``c2nim``
+  ##
+  ## Similar to `cImport() <cimport.html#cImport.m,>`_ but uses ``c2nim`` to generate
+  ## the Nim wrapper instead of ``toast``. Note that neither
+  ## `cOverride() <cimport.html#cOverride.m,>`_, `cSkipSymbol() <cimport.html#cSkipSymbol.m%2Cseq[string]>`_
+  ## nor `cPlugin() <cimport.html#cPlugin.m,>`_ have any impact on ``c2nim``.
+  ##
+  ## ``toast`` is only used to preprocess the header file and recurse
+  ## if specified.
+  ##
+  ## ``mode`` should be set to ``cpp`` for c2nim to wrap C++ headers.
+  ##
+  ## ``flags`` can be used to pass other command line arguments to ``c2nim``.
+  ##
+  ## ``nimterop`` does not depend on ``c2nim`` as a ``nimble`` dependency so it
+  ## does not get installed automatically. Any wrapper or library that requires this proc
+  ## needs to install ``c2nim`` with ``nimble install c2nim`` or add it as a dependency in
+  ## its own ``.nimble`` file.
+
+  result = newNimNode(nnkStmtList)
+
+  let
+    fullpath = findPath(filename)
+
+  echo "# Importing " & fullpath & " with c2nim"
+
+  let
+    output = getToast(fullpath, recurse, dynlib, noNimout = true)
+    hash = output.hash().abs()
+    hpath = getTempDir() / "nimterop_" & $hash & ".h"
+    npath = hpath[0 .. hpath.rfind('.')] & "nim"
+    header = ("header" & fullpath.splitFile().name.replace(re"[-.]+", ""))
+
+  if not fileExists(hpath) or gStateCT.nocache or compileOption("forceBuild"):
+    writeFile(hpath, output)
+
+  doAssert fileExists(hpath), "Unable to write temporary header file: " & hpath
+
+  var
+    cmd = &"c2nim {hpath} --header:{header}"
+
+  if dynlib.len != 0:
+    cmd.add &" --dynlib:{dynlib}"
+  if mode.contains("cpp"):
+    cmd.add " --cpp"
+  if flags.len != 0:
+    cmd.add &" {flags}"
+
+  for i in gStateCT.defines:
+    cmd.add &" --assumedef:{i.quoteShell}"
+
+  let
+    (c2nimout, ret) = gorgeEx(cmd, cache=getCacheValue(hpath))
+  doAssert ret == 0, c2nimout
+
+  var
+    nimout = &"const {header} = \"{fullpath}\"\n\n" & readFile(npath)
+
+  nimout = nimout.
+    replace(re"([u]?int[\d]+)_t", "$1").
+    replace(re"([u]?int)ptr_t", "ptr $1")
+
+  if gStateCT.debug:
+    echo nimout
+
+  try:
+    let body = parseStmt(nimout)
+
+    result.add body
+  except:
+    let
+      (tmpFile, errors) = getNimCheckError(nimout)
+    doAssert false, errors & "\n\nc2nim codegen limitation or error - review 'nim check' output above generated for " & tmpFile
diff --git a/nimterop/git.nim b/nimterop/git.nim
index 01afa9e..6e8fcac 100644
--- a/nimterop/git.nim
+++ b/nimterop/git.nim
@@ -3,6 +3,10 @@ import macros, os, osproc, regex, strformat, strutils
 import "."/[paths, compat]
 
 proc execAction*(cmd: string, nostderr=false): string =
+  ## Execute an external command - supported at compile time
+  ##
+  ## Checks if command exits successfully before returning. If not, an
+  ## error is raised.
   var
     ccmd = ""
     ret = 0
@@ -21,12 +25,17 @@ proc execAction*(cmd: string, nostderr=false): string =
   doAssert ret == 0, "Command failed: " & $(ret, nostderr) & "\nccmd: " & ccmd & "\nresult:\n" & result
 
 proc mkDir*(dir: string) =
+  ## Create a directory at cmopile time
+  ##
+  ## The `os` module is not available at compile time so a few
+  ## crucial helper functions are included with nimterop.
   if not dirExists(dir):
     let
       flag = when not defined(Windows): "-p" else: ""
     discard execAction(&"mkdir {flag} {dir.quoteShell}")
 
 proc cpFile*(source, dest: string, move=false) =
+  ## Copy a file from source to destination at compile time
   let
     source = source.replace("/", $DirSep)
     dest = dest.replace("/", $DirSep)
@@ -45,9 +54,12 @@ proc cpFile*(source, dest: string, move=false) =
   discard execAction(&"{cmd} {source.quoteShell} {dest.quoteShell}")
 
 proc mvFile*(source, dest: string) =
+  ## Move a file from source to destination at compile time
   cpFile(source, dest, move=true)
 
 proc extractZip*(zipfile, outdir: string) =
+  ## Extract a zip file using powershell on Windows and unzip on other
+  ## systems to the specified output directory
   var cmd = "unzip -o $#"
   if defined(Windows):
     cmd = "powershell -nologo -noprofile -command \"& { Add-Type -A " &
@@ -58,6 +70,10 @@ proc extractZip*(zipfile, outdir: string) =
   discard execAction(&"cd {outdir.quoteShell} && {cmd % zipfile}")
 
 proc downloadUrl*(url, outdir: string) =
+  ## Download a file using powershell on Windows and curl on other
+  ## systems to the specified output directory
+  ##
+  ## If a zip file, it is automatically extracted after download.
   let
     file = url.extractFilename()
     ext = file.splitFile().ext.toLowerAscii()
@@ -75,6 +91,7 @@ proc downloadUrl*(url, outdir: string) =
       extractZip(file, outdir)
 
 proc gitReset*(outdir: string) =
+  ## Hard reset the git repository at the specified directory
   echo "# Resetting " & outdir
 
   let cmd = &"cd {outdir.quoteShell} && git reset --hard"
@@ -83,6 +100,10 @@ proc gitReset*(outdir: string) =
     echo "#   Retrying ..."
 
 proc gitCheckout*(file, outdir: string) =
+  ## Checkout the specified file in the git repository specified
+  ##
+  ## This effectively resets all changes in the file and can be
+  ## used after `cImport()` if required.
   echo "# Resetting " & file
   let file2 = file.relativePath outdir
   let cmd = &"cd {outdir.quoteShell} && git checkout {file2.quoteShell}"
@@ -91,6 +112,10 @@ proc gitCheckout*(file, outdir: string) =
     echo "#   Retrying ..."
 
 proc gitPull*(url: string, outdir = "", plist = "", checkout = "") =
+  ## Pull the specified git repository to the output directory
+  ##
+  ## `plist` is the list of specific files and directories or wildcards
+  ## to sparse checkout. Multiples can be specified one entry per line.
   if dirExists(outdir/".git"):
     gitReset(outdir)
     return
@@ -105,7 +130,8 @@ proc gitPull*(url: string, outdir = "", plist = "", checkout = "") =
   discard execAction(&"cd {outdirQ} && git remote add origin {url}")
 
   if plist.len != 0:
-    # TODO: document this, it's not clear
+    # If a specific list of files is required, create a sparse checkout
+    # file for git in its config directory
     let sparsefile = outdir / ".git/info/sparse-checkout"
 
     discard execAction(&"cd {outdirQ} && git config core.sparsecheckout true")
@@ -119,7 +145,18 @@ proc gitPull*(url: string, outdir = "", plist = "", checkout = "") =
     echo "# Pulling repository"
     discard execAction(&"cd {outdirQ} && git pull --depth=1 origin master")
 
-proc configure*(path, check: string) =
+proc configure*(path, check: string, flags = "") =
+  ## Run the GNU `configure` command to generate all Makefiles or other
+  ## build scripts in the specified path
+  ##
+  ## If a `configure` script is not present and an `autogen.sh` script
+  ## is present, it will be run before attempting `configure`.
+  ##
+  ## `check` is a file that will be generated by the `configure` command.
+  ## This is required to prevent configure from running on every build. It
+  ## is relative to the `path` and should not be an absolute path.
+  ##
+  ## `flags` are any flags that should be passed to the `configure` command.
   if (path / check).fileExists():
     return
 
@@ -134,5 +171,55 @@ proc configure*(path, check: string) =
   if fileExists(path / "configure"):
     echo "#   Running configure"
 
-    discard execAction(&"cd {path.quoteShell} && bash configure")
+    var
+      cmd = &"cd {path.quoteShell} && bash configure"
+    if flags.len != 0:
+      cmd &= &" {flags}"
+
+    echo execAction(cmd)
+
+proc cmake*(path, check, flags: string) =
+  ## Run the `cmake` command to generate all Makefiles or other
+  ## build scripts in the specified path
+  ##
+  ## `path` will be created since typically `cmake` is run in an
+  ## empty directory.
+  ##
+  ## `check` is a file that will be generated by the `cmake` command.
+  ## This is required to prevent `cmake` from running on every build. It
+  ## is relative to the `path` and should not be an absolute path.
+  ##
+  ## `flags` are any flags that should be passed to the `cmake` command.
+  ## Unlike `configure`, it is required since typically it will be the
+  ## path to the repository, typically `..` when `path` is a subdir.
+  if (path / check).fileExists():
+    return
+
+  echo "# Running cmake " & path
+
+  mkDir(path)
+
+  var
+    cmd = &"cd {path.quoteShell} && cmake {flags}"
+
+  echo execAction(cmd)
+
+proc make*(path, check: string, flags = "") =
+  ## Run the `make` command to build all binaries in the specified path
+  ##
+  ## `check` is a file that will be generated by the `make` command.
+  ## This is required to prevent `make` from running on every build. It
+  ## is relative to the `path` and should not be an absolute path.
+  ##
+  ## `flags` are any flags that should be passed to the `make` command.
+  if (path / check).fileExists():
+    return
+
+  echo "# Running make " & path
+
+  var
+    cmd = &"cd {path.quoteShell} && make"
+  if flags.len != 0:
+    cmd &= &" {flags}"
 
+  echo execAction(cmd)
\ No newline at end of file