add support for export and import symbols

adds a lot of improvement to the script
- proper CLI
- generate a api_require.h which contains a function that export the symbols

scripts/generate_header.sh

@@ -23,16 +23,19 @@ discard_preprocessors() {
 # sed regex for extracting data from function signature
 # if this isn't regex, idk what is
 # LUA_API (return type as \2) (function name as \3) (args as \4)
-sym_regex='^LUA\(LIB\)\?_API\s\+\([^(]\+\)\s*(\([^)]\+\))\s\+(\([^)]\+\))'
+sym_regex='^LUA\(LIB\)\?_API\s\+\([^(]\+\)\s*(\([^)]\+\))\s\+(\([^)]\+\));'
 
 # get funcptr declarations
 ptrize() {
-  grep '^LUA' | sed -e "s/$sym_regex/static \2(*\3) (\4)/"
+  grep '^LUA' | sed -e "s/$sym_regex/static \2(*\3) (\4);/"
+}
+
+import_sym() {
+  grep '^LUA' | sed -e "s/$sym_regex/\tIMPORT_SYMBOL(\3, \2, \4);/"
 }
 
 export_sym() {
-  # don't even bother reading this again
+  grep '^LUA' | sed -e "s/$sym_regex/\t\tEXPORT_SYMBOL(\3),/"
-  grep '^LUA' | sed -e "s/$sym_regex/\tIMPORT_SYMBOL(\3, \2, \4)/"
 }
 
 decl() {
@@ -47,48 +50,134 @@ decl() {
   grep '^#' <<< "$header"
 }
 
+decl_import() {
+  uncomment $1 | onelineize | import_sym
+}
+
 decl_export() {
   uncomment $1 | onelineize | export_sym
 }
 
-LUA_PATH="$1"
 
-cat << EOF
+generate_header() {
-/**
+  local LUA_PATH="$1"
-The lite_xl plugin API is quite simple. Any shared library can be a plugin file, so long
+  echo "#ifndef LITE_XL_PLUGIN_API"
-as it has an entrypoint that looks like the following, where xxxxx is the plugin name:
+  echo "#define LITE_XL_PLUGIN_API"
-#include "lite_xl_plugin_api.h"
+  echo "/**"
-int lua_open_lite_xl_xxxxx(lua_State* L, void* XL) {
+  echo "The lite_xl plugin API is quite simple. Any shared library can be a plugin file, so long"
-  lite_xl_plugin_init(XL);
+  echo "as it has an entrypoint that looks like the following, where xxxxx is the plugin name:"
-  ...
+  echo '#include "lite_xl_plugin_api.h"'
-  return 1;
+  echo "int lua_open_lite_xl_xxxxx(lua_State* L, void* XL) {"
+  echo "  lite_xl_plugin_init(XL);"
+  echo "  ..."
+  echo "  return 1;"
+  echo "}"
+  echo "In linux, to compile this file, you'd do: 'gcc -o xxxxx.so -shared xxxxx.c'. Simple!"
+  echo "Due to the way the API is structured, you *should not* link or include lua libraries."
+  echo "This file was automatically generated by the below code. DO NOT MODIFY DIRECTLY."
+  echo
+  echo
+  cat "$0"
+  echo "**/"
+  echo "#include <stddef.h>"
+
+  decl "$LUA_PATH/lua.h"
+  decl "$LUA_PATH/lauxlib.h"
+
+  echo "#define IMPORT_SYMBOL(name, ret, ...) name = (ret (*) (__VA_ARGS__)) symbol(#name)"
+  echo "static void lite_xl_plugin_init(void *XL) {"
+  echo -e "\tvoid* (*symbol)(const char *) = (void* (*) (const char *)) XL;"
+
+  decl_import "$LUA_PATH/lua.h"
+  decl_import "$LUA_PATH/lauxlib.h"
+
+  echo "}"
+  echo "#endif"
 }
-In linux, to compile this file, you'd do: 'gcc -o xxxxx.so -shared xxxxx.c'. Simple!
-Due to the way the API is structured, you *should not* link or include lua libraries.
-This file was automatically generated by the below code. Do NOT MODIFY DIRECTLY.
 
+generate_api_require() {
+  local LUA_PATH="$1"
+  echo "#ifndef API_REQUIRE_H"
+  echo "#define API_REQUIRE_H"
+  echo "/**"
+  echo "This file contains the function api_require that"
+  echo "returns a function pointer with it's corresponding name."
+  echo
+  echo "This file is automatically generated. DO NOT MODIFY."
+  echo "*/"
+  echo "#include <string.h>"
+  echo "#include <stddef.h>"
+  echo '#include "lua.h"'
+  echo '#include "lauxlib.h"'
+  echo
+  echo "typedef struct fnptr_s {"
+  echo -e "\tconst char* name;"
+  echo -e "\tvoid *addr;"
+  echo "} fnptr_t;"
+  echo
+  echo "#define EXPORT_SYMBOL(SYM) { #SYM, (void*)(SYM) }"
+  echo "static void *api_require(const char *symbol) {"
+  echo -e "\tstatic fnptr_t nodes[] = {"
 
-EOF
+  decl_export "$LUA_PATH/lua.h"
+  decl_export "$LUA_PATH/lauxlib.h"
 
-cat "$0"
+  echo -e "\t};"
+  echo -e "\tfor (int i = 0; i < sizeof(nodes) / sizeof(fnptr_t); i++)"
+  echo -e "\t\tif (strcmp(nodes[i].name, symbol) == 0)"
+  echo -e "\t\t\treturn nodes[i].addr;"
+  echo -e "\treturn NULL;"
+  echo "}"
+  echo "#endif"
+}
 
-cat << EOF
+show_help() {
-**/
+  echo -e "Usage: $0 <OPTIONS> prefix"
+  echo
+  echo -e "Available options:"
+  echo
+  echo -e "-a\t--api-header\tGenerate lite_xl_plugin_api.h"
+  echo -e "-b\t--api-require\tGenerate api_require.h"
+  echo -e "-p\t--prefix\tSet prefix (where to find lua.h and lauxlib.h)"
+}
 
+main() {
+  local header=0
+  local require=0
+  local prefix=""
 
-#ifndef LITE_XL_PLUGIN_API
+  for i in "$@"; do
-#define LITE_XL_PLUGIN_API
+    case $i in
-EOF
+      -h|--help)
+        show_help
+        exit 0
+        ;;
+      -a|--api-header)
+        header=1
+        shift
+        ;;
+      -b|--api-require)
+        require=1
+        shift
+        ;;
+      -p|--prefix)
+        prefix="$2"
+        shift
+        shift
+        ;;
+      *)
+        ;;
+    esac
+  done
 
-decl "$LUA_PATH/lua.h"
+  if [[ "$header" -eq 1 ]]; then
-decl "$LUA_PATH/lauxlib.h"
+    generate_header "$prefix"
+  elif [[ "$require" -eq 1 ]]; then
+    generate_api_require "$prefix"
+  else
+    show_help
+    exit 1
+  fi
+}
 
-echo "#define IMPORT_SYMBOL(name, ret, ...) name = (ret (*) (__VA_ARGS__)) symbol(#name)"
+main "$@"
-echo "static void lite_xl_plugin_init(void *XL) {"
-echo -e "\tvoid* (*symbol)(const char *) = (void* (*) (const char *)) XL;"
-
-decl_export "$LUA_PATH/lua.h"
-decl_export "$LUA_PATH/lauxlib.h"
-
-echo "}"
-echo "#endif"