Initial commit.

9 files changed, 1174 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..99f9e35
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+lpm
+*.o
+lpm.lua.c
diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..3755286
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,12 @@
+[submodule "lua"]
+	path = lib/lua
+	url = https://github.com/lua/lua.git
+[submodule "lib/libgit2"]
+	path = lib/libgit2
+	url = https://github.com/libgit2/libgit2.git
+[submodule "lib/openssl"]
+	path = lib/openssl
+	url = https://github.com/openssl/openssl.git
+[submodule "lib/zlib"]
+	path = lib/zlib
+	url = https://github.com/madler/zlib.git
diff --git a/build.sh b/build.sh
new file mode 100755
index 0000000..497767d
--- /dev/null
+++ b/build.sh
@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+
+: ${CC=gcc}
+: ${MAKE=make}
+: ${BIN=lpm}
+: ${JOBS=4}
+
+SRCS="*.c"
+LDFLAGS="$LDFLAGS -lm -pthread -static-libgcc"
+
+[[ "$@" == "clean" ]] && rm -rf lib/libgit2/build lib/zlib/build lib/openssl/build $BIN && exit 0
+
+# Build supporting libraries, libgit2, libz, libssl (with libcrypto), libpcre
+if [[ "$@" != *"-libgit2"* ]]; then
+  [ ! -e "lib/libgit2/include" ] && echo "Make sure you've cloned submodules. (git submodule update --init --depth=1)" && exit -1
+  [ ! -e "lib/libgit2/build" ] && cd lib/libgit2 && mkdir build && cmake .. -DBUILD_SHARED_LIBS=OFF -DUSE_SSH=OFF && $MAKE -j $JOBS && cd ../../
+  LDFLAGS="$LDFLAGS -Llib/libgit2/build -l:libgit2.a" && CFLAGS="$CFLAGS -Ilib/libgit2/build/include/git2 -Ilib/libgit2/build/include -Ilib/libgit2/include"
+fi
+if [[ "$@" != *"-lz"* ]]; then
+  [ ! -e "lib/zlib/build" ] && cd lib/zlib && mkdir build && ../configure && $MAKE -j $JOBS && cd ../../
+  LDFLAGS="$LDFLAGS -Llib/libz/build -l:libz.a" && CFLAGS="$CFLAGS -Ilib/libz"
+fi
+if [[ "$@" != *"-lssl"* ]]; then
+  [ ! -e "lib/openssl/build" ] && cd lib/openssl && mkdir build && ../Configure && $MAKE -j $JOBS && cd ../../
+  LDFLAGS="$LDFLAGS -Llib/libz/build -l:libssl.a -l:libcrypto.a" && CFLAGS="$CFLAGS -Ilib/libz"
+fi
+[[ "$@" != *"-llua"* ]] && CFLAGS="$CFLAGS -Ilib/lua -DMAKE_LIB=1" && SRCS="$SRCS lib/lua/onelua.c"
+
+# Build the pre-packaged lua file into the executbale.
+echo "const char* luafile = " > lpm.lua.c && cat lpm.lua | sed 's/\\/\\\\/g' | sed 's/"/\\"/g' | sed 's/^/"/' | sed 's/$/\\n"/' >> lpm.lua.c && echo ";" >> lpm.lua.c
+
+[[ "$@" != *" -g "* || "$@" != *" -O"* ]] && CFLAGS="$CFLAGS -O3" && LDFLAGS="$LDFLAGS -s"
+$CC $CFLAGS $SRCS $@ -o lpm $LDFLAGS -ldl  -l:libpcre.a
diff --git a/lib/libgit2 b/lib/libgit2
new file mode 160000
+Subproject 22f382539d78f69aa91721ad62bbd7229750a04
diff --git a/lib/lua b/lib/lua
new file mode 160000
+Subproject 997f11f54322883c3181225f29d101a597f3173
diff --git a/lib/openssl b/lib/openssl
new file mode 160000
+Subproject fd24de9f93049b05a54c48da5316f4288248923
diff --git a/lib/zlib b/lib/zlib
new file mode 160000
+Subproject 21767c654d31d2dccdde4330529775c6c5fd538
diff --git a/lpm.c b/lpm.c
new file mode 100644
index 0000000..2da8a13
--- /dev/null
+++ b/lpm.c
@@ -0,0 +1,396 @@
+/* lpm.c - Core of the lite package manager. 
+
+LPM is a package manager for `lite-xl`, written in C (and packed-in lua).
+
+It has the following commands:
+
+lpm add <repository remote>
+lpm rm <repository remote>
+lpm update [<repository remote>]
+lpm install <plugin name>
+lpm uninstall <plugin name>
+lpm list
+
+It stores files in a cache directory in the follwoing format:
+
+<remote url>:<branch_name|commit_name>
+
+*/
+
+#include <git2.h>
+#include <string.h>
+#include <stdio.h>
+#include <errno.h>
+#include <lua.h>
+#include <lauxlib.h>
+#include <ctype.h>
+#include <lualib.h>
+#include <dirent.h>
+#include <unistd.h>
+
+#include <sys/stat.h>
+#include <git2.h>
+
+#ifdef _WIN32
+  #include <direct.h>
+  #include <windows.h>
+  #include <fileapi.h>
+#endif
+
+/* 64bit fnv-1a hash */
+typedef unsigned long long hash_t;
+static char hexDigits[] = "0123456789abcdef";
+#define FNV_64_PRIME ((hash_t)0x100000001b3ULL)
+static int lpm_hash(lua_State* L) {
+  hash_t hval = 0;
+  size_t len;
+  const char* data = luaL_checklstring(L, 1, &len);
+  const unsigned char *bp = (unsigned char*)data;
+  const unsigned char *be = data + len;
+  while (bp < be) {
+    hval *= FNV_64_PRIME;
+    hval ^= (unsigned long long)*bp++;
+  }
+  char buffer[16];
+  for (size_t i = 0; i < len; ++i) {
+    buffer[i*2+0] = hexDigits[data[i] >> 4];
+    buffer[i*2+1] = hexDigits[data[i] & 0xF];
+  }
+  lua_pushlstring(L, buffer, 16);
+  return 1;
+}
+
+/** BEGIN STOLEN LITE CODE **/
+static int lpm_ls(lua_State *L) {
+  const char *path = luaL_checkstring(L, 1);
+
+#ifdef _WIN32
+  lua_settop(L, 1);
+  if (strchr("\\/", path[strlen(path) - 2]) != NULL)
+    lua_pushstring(L, "*");
+  else
+    lua_pushstring(L, "/*");
+
+  lua_concat(L, 2);
+  path = lua_tostring(L, -1);
+
+  LPWSTR wpath = utfconv_utf8towc(path);
+  if (wpath == NULL) {
+    lua_pushnil(L);
+    lua_pushstring(L, UTFCONV_ERROR_INVALID_CONVERSION);
+    return 2;
+  }
+
+  WIN32_FIND_DATAW fd;
+  HANDLE find_handle = FindFirstFileExW(wpath, FindExInfoBasic, &fd, FindExSearchNameMatch, NULL, 0);
+  free(wpath);
+  if (find_handle == INVALID_HANDLE_VALUE) {
+    lua_pushnil(L);
+    push_win32_error(L, GetLastError());
+    return 2;
+  }
+
+  char mbpath[MAX_PATH * 4]; // utf-8 spans 4 bytes at most
+  int len, i = 1;
+  lua_newtable(L);
+
+  do
+  {
+    if (wcscmp(fd.cFileName, L".") == 0) { continue; }
+    if (wcscmp(fd.cFileName, L"..") == 0) { continue; }
+
+    len = WideCharToMultiByte(CP_UTF8, 0, fd.cFileName, -1, mbpath, MAX_PATH * 4, NULL, NULL);
+    if (len == 0) { break; }
+    lua_pushlstring(L, mbpath, len - 1); // len includes \0
+    lua_rawseti(L, -2, i++);
+  } while (FindNextFileW(find_handle, &fd));
+
+  if (GetLastError() != ERROR_NO_MORE_FILES) {
+    lua_pushnil(L);
+    push_win32_error(L, GetLastError());
+    FindClose(find_handle);
+    return 2;
+  }
+
+  FindClose(find_handle);
+  return 1;
+#else
+  DIR *dir = opendir(path);
+  if (!dir) {
+    lua_pushnil(L);
+    lua_pushstring(L, strerror(errno));
+    return 2;
+  }
+
+  lua_newtable(L);
+  int i = 1;
+  struct dirent *entry;
+  while ( (entry = readdir(dir)) ) {
+    if (strcmp(entry->d_name, "." ) == 0) { continue; }
+    if (strcmp(entry->d_name, "..") == 0) { continue; }
+    lua_pushstring(L, entry->d_name);
+    lua_rawseti(L, -2, i);
+    i++;
+  }
+
+  closedir(dir);
+  return 1;
+#endif
+}
+
+static int lpm_rmdir(lua_State *L) {
+  const char *path = luaL_checkstring(L, 1);
+
+#ifdef _WIN32
+  LPWSTR wpath = utfconv_utf8towc(path);
+  int deleted = RemoveDirectoryW(wpath);
+  free(wpath);
+  if (deleted > 0) {
+    lua_pushboolean(L, 1);
+  } else {
+    lua_pushboolean(L, 0);
+    push_win32_error(L, GetLastError());
+    return 2;
+  }
+#else
+  int deleted = remove(path);
+  if(deleted < 0) {
+    lua_pushboolean(L, 0);
+    lua_pushstring(L, strerror(errno));
+
+    return 2;
+  } else {
+    lua_pushboolean(L, 1);
+  }
+#endif
+
+  return 1;
+}
+
+static int lpm_mkdir(lua_State *L) {
+  const char *path = luaL_checkstring(L, 1);
+
+#ifdef _WIN32
+  LPWSTR wpath = utfconv_utf8towc(path);
+  if (wpath == NULL) {
+    lua_pushboolean(L, 0);
+    lua_pushstring(L, UTFCONV_ERROR_INVALID_CONVERSION);
+    return 2;
+  }
+
+  int err = _wmkdir(wpath);
+  free(wpath);
+#else
+  int err = mkdir(path, S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH);
+#endif
+  if (err < 0) {
+    lua_pushboolean(L, 0);
+    lua_pushstring(L, strerror(errno));
+    return 2;
+  }
+
+  lua_pushboolean(L, 1);
+  return 1;
+}
+
+static int lpm_stat(lua_State *L) {
+  const char *path = luaL_checkstring(L, 1);
+
+#ifdef _WIN32
+  struct _stat s;
+  LPWSTR wpath = utfconv_utf8towc(path);
+  if (wpath == NULL) {
+    lua_pushnil(L);
+    lua_pushstring(L, UTFCONV_ERROR_INVALID_CONVERSION);
+    return 2;
+  }
+  int err = _wstat(wpath, &s);
+  free(wpath);
+#else
+  struct stat s;
+  int err = stat(path, &s);
+#endif
+  if (err < 0) {
+    lua_pushnil(L);
+    lua_pushstring(L, strerror(errno));
+    return 2;
+  }
+
+  lua_newtable(L);
+  lua_pushinteger(L, s.st_mtime);
+  lua_setfield(L, -2, "modified");
+
+  lua_pushinteger(L, s.st_size);
+  lua_setfield(L, -2, "size");
+
+  if (S_ISREG(s.st_mode)) {
+    lua_pushstring(L, "file");
+  } else if (S_ISDIR(s.st_mode)) {
+    lua_pushstring(L, "dir");
+  } else {
+    lua_pushnil(L);
+  }
+  lua_setfield(L, -2, "type");
+
+#if __linux__
+  if (S_ISDIR(s.st_mode)) {
+    if (lstat(path, &s) == 0) {
+      lua_pushboolean(L, S_ISLNK(s.st_mode));
+      lua_setfield(L, -2, "symlink");
+    }
+  }
+#endif
+  return 1;
+}
+/** END STOLEN LITE CODE **/
+
+static const char* git_error_last_string() {
+  const git_error* last_error = git_error_last();
+  return last_error->message;
+}
+
+static int git_get_id(git_oid* commit_id, git_repository* repository, const char* name) {
+  int length = strlen(name);
+  int is_hex = length == 40;
+  for (int i = 0; is_hex && i < length; ++i)
+    is_hex = isxdigit(name[i]);
+  if (!is_hex)
+    return git_reference_name_to_id(commit_id, repository, name);
+  return git_oid_fromstr(commit_id, name);
+}
+
+static git_repository* luaL_checkgitrepo(lua_State* L, int index) {
+  const char* path = luaL_checkstring(L, index);
+  git_repository* repository;
+  if (git_repository_open(&repository, path))
+    return (void*)(long long)luaL_error(L, "git open error: %s", git_error_last_string());
+  return repository;
+}
+
+
+static git_commit* git_retrieve_commit(git_repository* repository, const char* commit_name) {
+  git_oid commit_id;
+  git_commit* commit;
+  if (git_get_id(&commit_id, repository, commit_name))
+    return NULL;
+  if (git_commit_lookup(&commit, repository, &commit_id))
+    return NULL;
+  return commit;
+}
+
+
+int lpm_reset(lua_State* L) {
+  git_repository* repository = luaL_checkgitrepo(L, 1);
+  const char* commit_name = luaL_checkstring(L, 2);
+  const char* type = luaL_checkstring(L, 3);
+  git_commit* commit = git_retrieve_commit(repository, commit_name);
+  if (!commit) {
+    git_repository_free(repository);
+    return luaL_error(L, "git retrieve commit error: %s", git_error_last_string());
+  }
+  git_reset_t reset_type = GIT_RESET_SOFT;
+  if (strcmp(type, "mixed") == 0)
+    reset_type = GIT_RESET_MIXED;
+  else if (strcmp(type, "hard") == 0)
+    reset_type = GIT_RESET_HARD;
+  int result = git_reset(repository, (git_object*)commit, reset_type, NULL);
+  git_commit_free(commit);
+  git_repository_free(repository);
+  if (result)
+    return luaL_error(L, "git reset error: %s", git_error_last_string());
+  return 0;
+}
+
+
+int lpm_init(lua_State* L) {
+  const char* path = luaL_checkstring(L, 1);
+  const char* url = luaL_checkstring(L, 2);
+  git_repository* repository;
+  if (git_repository_init(&repository, path, 0) != 0)
+    return luaL_error(L, "git init error: %s", git_error_last_string());
+  git_remote* remote;
+  if (git_remote_create(&remote, repository, "origin", url)) {
+    git_repository_free(repository);
+    return luaL_error(L, "git remote add error: %s", git_error_last_string());
+  }
+  git_remote_free(remote);
+  git_repository_free(repository);
+  return 0;
+}
+
+
+int lpm_fetch(lua_State* L) {
+  git_repository* repository = luaL_checkgitrepo(L, 1);
+  git_remote* remote;
+  if (git_remote_lookup(&remote, repository, "origin")) {
+    git_repository_free(repository);
+    return luaL_error(L, "git remote fetch error: %s", git_error_last_string());
+  }
+  git_fetch_options fetch_opts = GIT_FETCH_OPTIONS_INIT;
+  if (git_remote_fetch(remote, NULL, &fetch_opts, NULL)) {
+    git_remote_free(remote);
+    git_repository_free(repository);
+    return luaL_error(L, "git remote fetch error: %s", git_error_last_string());
+  }
+  git_remote_free(remote);
+  git_repository_free(repository);
+  return 0;
+}
+
+
+int lpm_status(lua_State* L) {
+  const char* path = luaL_checkstring(L, 1);
+  git_repository* repository;
+  if (git_repository_open(&repository, path))
+    return luaL_error(L, "git open error: %s", git_error_last_string());
+  git_repository_free(repository);
+  lua_newtable(L);
+  lua_pushnil(L);
+  lua_setfield(L, -2, "commit");
+  lua_pushnil(L);
+  lua_setfield(L, -2, "branch");
+  return 1;
+}
+
+
+static const luaL_Reg system_lib[] = {
+  { "ls",    lpm_ls    }, // Returns an array of files.
+  { "stat",  lpm_stat  }, // Returns info about a single file.
+  { "mkdir", lpm_mkdir }, // Makes a directory.
+  { "rmdir", lpm_rmdir }, // Removes a directory.
+  { "hash",  lpm_hash  }, // Returns a hexhash.
+  { "init",  lpm_init }, // Initializes a git repository with the specified remote.
+  { "fetch",  lpm_fetch }, // Updates a git repository with the specified remote.
+  { "reset",  lpm_reset }, // Updates a git repository to the specified commit/hash/branch.
+  { "status", lpm_status } // Returns the git repository in question's current branch, if any, and commit hash.
+};
+
+extern const char* luafile;
+int main(int argc, char* argv[]) {
+  git_libgit2_init();
+  lua_State* L = luaL_newstate();
+  luaL_openlibs(L);
+  luaL_newlib(L, system_lib); lua_setglobal(L, "system");
+  lua_newtable(L);
+  for (int i = 0; i < argc; ++i) {
+    lua_pushstring(L, argv[i]);
+    lua_rawseti(L, -2, i+1);
+  }
+  lua_setglobal(L, "ARGV");
+  #if _WIN32 
+    lua_pushliteral(L, "\\");
+  #else
+    lua_pushliteral(L, "/");
+  #endif
+  lua_setglobal(L, "PATHSEP");
+  //if (luaL_loadstring(L, luafile)) {
+  if (luaL_loadfile(L, "lpm.lua")) {
+    fprintf(stderr, "internal error when starting the application: %s\n", lua_tostring(L, -1));
+    return -1;
+  }
+  lua_pcall(L, 0, 1, 0);
+  int status = lua_tointeger(L, -1);
+  lua_close(L);
+  git_libgit2_shutdown();
+  return status;
+}
diff --git a/lpm.lua b/lpm.lua
new file mode 100644
index 0000000..d0e53e7
--- /dev/null
+++ b/lpm.lua
@@ -0,0 +1,730 @@
+local strict = {}
+strict.defined = {}
+
+-- used to define a global variable
+function global(t)
+  for k, v in pairs(t) do
+    strict.defined[k] = true
+    rawset(_G, k, v)
+  end
+end
+
+function strict.__newindex(t, k, v)
+  error("cannot set undefined variable: " .. k, 2)
+end
+
+function strict.__index(t, k)
+  if not strict.defined[k] then
+    error("cannot get undefined variable: " .. k, 2)
+  end
+end
+
+setmetatable(_G, strict)
+
+
+-- Begin JSON library.
+--
+-- json.lua
+--
+-- Copyright (c) 2020 rxi
+--
+-- Permission is hereby granted, free of charge, to any person obtaining a copy of
+-- this software and associated documentation files (the "Software"), to deal in
+-- the Software without restriction, including without limitation the rights to
+-- use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+-- of the Software, and to permit persons to whom the Software is furnished to do
+-- so, subject to the following conditions:
+--
+-- The above copyright notice and this permission notice shall be included in all
+-- copies or substantial portions of the Software.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+-- SOFTWARE.
+--
+
+local json = { _version = "0.1.2" }
+
+-------------------------------------------------------------------------------
+-- Encode
+-------------------------------------------------------------------------------
+
+local encode
+
+local escape_char_map = {
+  [ "\\" ] = "\\",
+  [ "\"" ] = "\"",
+  [ "\b" ] = "b",
+  [ "\f" ] = "f",
+  [ "\n" ] = "n",
+  [ "\r" ] = "r",
+  [ "\t" ] = "t",
+}
+
+local escape_char_map_inv = { [ "/" ] = "/" }
+for k, v in pairs(escape_char_map) do
+  escape_char_map_inv[v] = k
+end
+
+
+local function escape_char(c)
+  return "\\" .. (escape_char_map[c] or string.format("u%04x", c:byte()))
+end
+
+
+local function encode_nil(val)
+  return "null"
+end
+
+
+local function encode_table(val, stack)
+  local res = {}
+  stack = stack or {}
+
+  -- Circular reference?
+  if stack[val] then error("circular reference") end
+
+  stack[val] = true
+
+  if rawget(val, 1) ~= nil or next(val) == nil then
+    -- Treat as array -- check keys are valid and it is not sparse
+    local n = 0
+    for k in pairs(val) do
+      if type(k) ~= "number" then
+        error("invalid table: mixed or invalid key types")
+      end
+      n = n + 1
+    end
+    if n ~= #val then
+      error("invalid table: sparse array")
+    end
+    -- Encode
+    for i, v in ipairs(val) do
+      table.insert(res, encode(v, stack))
+    end
+    stack[val] = nil
+    return "[" .. table.concat(res, ",") .. "]"
+
+  else
+    -- Treat as an object
+    for k, v in pairs(val) do
+      if type(k) ~= "string" then
+        error("invalid table: mixed or invalid key types")
+      end
+      table.insert(res, encode(k, stack) .. ":" .. encode(v, stack))
+    end
+    stack[val] = nil
+    return "{" .. table.concat(res, ",") .. "}"
+  end
+end
+
+
+local function encode_string(val)
+  return '"' .. val:gsub('[%z\1-\31\\"]', escape_char) .. '"'
+end
+
+
+local function encode_number(val)
+  -- Check for NaN, -inf and inf
+  if val ~= val or val <= -math.huge or val >= math.huge then
+    error("unexpected number value '" .. tostring(val) .. "'")
+  end
+  return string.format("%.14g", val)
+end
+
+
+local type_func_map = {
+  [ "nil"     ] = encode_nil,
+  [ "table"   ] = encode_table,
+  [ "string"  ] = encode_string,
+  [ "number"  ] = encode_number,
+  [ "boolean" ] = tostring,
+}
+
+
+encode = function(val, stack)
+  local t = type(val)
+  local f = type_func_map[t]
+  if f then
+    return f(val, stack)
+  end
+  error("unexpected type '" .. t .. "'")
+end
+
+
+function json.encode(val)
+  return ( encode(val) )
+end
+
+
+-------------------------------------------------------------------------------
+-- Decode
+-------------------------------------------------------------------------------
+
+local parse
+
+local function create_set(...)
+  local res = {}
+  for i = 1, select("#", ...) do
+    res[ select(i, ...) ] = true
+  end
+  return res
+end
+
+local space_chars   = create_set(" ", "\t", "\r", "\n")
+local delim_chars   = create_set(" ", "\t", "\r", "\n", "]", "}", ",")
+local escape_chars  = create_set("\\", "/", '"', "b", "f", "n", "r", "t", "u")
+local literals      = create_set("true", "false", "null")
+
+local literal_map = {
+  [ "true"  ] = true,
+  [ "false" ] = false,
+  [ "null"  ] = nil,
+}
+
+
+local function next_char(str, idx, set, negate)
+  for i = idx, #str do
+    if set[str:sub(i, i)] ~= negate then
+      return i
+    end
+  end
+  return #str + 1
+end
+
+
+local function decode_error(str, idx, msg)
+  local line_count = 1
+  local col_count = 1
+  for i = 1, idx - 1 do
+    col_count = col_count + 1
+    if str:sub(i, i) == "\n" then
+      line_count = line_count + 1
+      col_count = 1
+    end
+  end
+  error( string.format("%s at line %d col %d", msg, line_count, col_count) )
+end
+
+
+local function codepoint_to_utf8(n)
+  -- http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=iws-appendixa
+  local f = math.floor
+  if n <= 0x7f then
+    return string.char(n)
+  elseif n <= 0x7ff then
+    return string.char(f(n / 64) + 192, n % 64 + 128)
+  elseif n <= 0xffff then
+    return string.char(f(n / 4096) + 224, f(n % 4096 / 64) + 128, n % 64 + 128)
+  elseif n <= 0x10ffff then
+    return string.char(f(n / 262144) + 240, f(n % 262144 / 4096) + 128,
+                       f(n % 4096 / 64) + 128, n % 64 + 128)
+  end
+  error( string.format("invalid unicode codepoint '%x'", n) )
+end
+
+
+local function parse_unicode_escape(s)
+  local n1 = tonumber( s:sub(1, 4),  16 )
+  local n2 = tonumber( s:sub(7, 10), 16 )
+   -- Surrogate pair?
+  if n2 then
+    return codepoint_to_utf8((n1 - 0xd800) * 0x400 + (n2 - 0xdc00) + 0x10000)
+  else
+    return codepoint_to_utf8(n1)
+  end
+end
+
+
+local function parse_string(str, i)
+  local res = ""
+  local j = i + 1
+  local k = j
+
+  while j <= #str do
+    local x = str:byte(j)
+
+    if x < 32 then
+      decode_error(str, j, "control character in string")
+
+    elseif x == 92 then -- `\`: Escape
+      res = res .. str:sub(k, j - 1)
+      j = j + 1
+      local c = str:sub(j, j)
+      if c == "u" then
+        local hex = str:match("^[dD][89aAbB]%x%x\\u%x%x%x%x", j + 1)
+                 or str:match("^%x%x%x%x", j + 1)
+                 or decode_error(str, j - 1, "invalid unicode escape in string")
+        res = res .. parse_unicode_escape(hex)
+        j = j + #hex
+      else
+        if not escape_chars[c] then
+          decode_error(str, j - 1, "invalid escape char '" .. c .. "' in string")
+        end
+        res = res .. escape_char_map_inv[c]
+      end
+      k = j + 1
+
+    elseif x == 34 then -- `"`: End of string
+      res = res .. str:sub(k, j - 1)
+      return res, j + 1
+    end
+
+    j = j + 1
+  end
+
+  decode_error(str, i, "expected closing quote for string")
+end
+
+
+local function parse_number(str, i)
+  local x = next_char(str, i, delim_chars)
+  local s = str:sub(i, x - 1)
+  local n = tonumber(s)
+  if not n then
+    decode_error(str, i, "invalid number '" .. s .. "'")
+  end
+  return n, x
+end
+
+
+local function parse_literal(str, i)
+  local x = next_char(str, i, delim_chars)
+  local word = str:sub(i, x - 1)
+  if not literals[word] then
+    decode_error(str, i, "invalid literal '" .. word .. "'")
+  end
+  return literal_map[word], x
+end
+
+
+local function parse_array(str, i)
+  local res = {}
+  local n = 1
+  i = i + 1
+  while 1 do
+    local x
+    i = next_char(str, i, space_chars, true)
+    -- Empty / end of array?
+    if str:sub(i, i) == "]" then
+      i = i + 1
+      break
+    end
+    -- Read token
+    x, i = parse(str, i)
+    res[n] = x
+    n = n + 1
+    -- Next token
+    i = next_char(str, i, space_chars, true)
+    local chr = str:sub(i, i)
+    i = i + 1
+    if chr == "]" then break end
+    if chr ~= "," then decode_error(str, i, "expected ']' or ','") end
+  end
+  return res, i
+end
+
+
+local function parse_object(str, i)
+  local res = {}
+  i = i + 1
+  while 1 do
+    local key, val
+    i = next_char(str, i, space_chars, true)
+    -- Empty / end of object?
+    if str:sub(i, i) == "}" then
+      i = i + 1
+      break
+    end
+    -- Read key
+    if str:sub(i, i) ~= '"' then
+      decode_error(str, i, "expected string for key")
+    end
+    key, i = parse(str, i)
+    -- Read ':' delimiter
+    i = next_char(str, i, space_chars, true)
+    if str:sub(i, i) ~= ":" then
+      decode_error(str, i, "expected ':' after key")
+    end
+    i = next_char(str, i + 1, space_chars, true)
+    -- Read value
+    val, i = parse(str, i)
+    -- Set
+    res[key] = val
+    -- Next token
+    i = next_char(str, i, space_chars, true)
+    local chr = str:sub(i, i)
+    i = i + 1
+    if chr == "}" then break end
+    if chr ~= "," then decode_error(str, i, "expected '}' or ','") end
+  end
+  return res, i
+end
+
+
+local char_func_map = {
+  [ '"' ] = parse_string,
+  [ "0" ] = parse_number,
+  [ "1" ] = parse_number,
+  [ "2" ] = parse_number,
+  [ "3" ] = parse_number,
+  [ "4" ] = parse_number,
+  [ "5" ] = parse_number,
+  [ "6" ] = parse_number,
+  [ "7" ] = parse_number,
+  [ "8" ] = parse_number,
+  [ "9" ] = parse_number,
+  [ "-" ] = parse_number,
+  [ "t" ] = parse_literal,
+  [ "f" ] = parse_literal,
+  [ "n" ] = parse_literal,
+  [ "[" ] = parse_array,
+  [ "{" ] = parse_object,
+}
+
+
+parse = function(str, idx)
+  local chr = str:sub(idx, idx)
+  local f = char_func_map[chr]
+  if f then
+    return f(str, idx)
+  end
+  decode_error(str, idx, "unexpected character '" .. chr .. "'")
+end
+
+
+function json.decode(str)
+  if type(str) ~= "string" then
+    error("expected argument of type string, got " .. type(str))
+  end
+  local res, idx = parse(str, next_char(str, 1, space_chars, true))
+  idx = next_char(str, idx, space_chars, true)
+  if idx <= #str then
+    decode_error(str, idx, "trailing garbage")
+  end
+  return res
+end
+
+-- End JSON library.
+
+local common = {}
+
+function common.rmrf(root)
+  if not root or root == "" then return end
+  local info = system.stat(root)
+  if not info then return end
+  if info.type == "file" then return os.remove(root) end
+  for i,v in ipairs(system.ls(root)) do common.rmrf(root .. PATHSEP .. v) end
+  system.rmdir(root)
+end
+
+function common.mkdirp(path)
+  local stat = system.stat(path)
+  if stat and stat.type == "dir" then return true end
+  if stat and stat.type == "file" then error("path " .. path .. " exists") end
+  local subdirs = {}
+  while path and path ~= "" do
+    system.mkdir(path)
+    local updir, basedir = path:match("(.*)[/\\](.+)$")
+    table.insert(subdirs, 1, basedir or path)
+    path = updir
+  end
+  for _, dirname in ipairs(subdirs) do
+    path = path and path .. PATHSEP .. dirname or dirname
+    system.mkdir(path)
+  end
+end
+
+
+function common.basename(path)
+  local s = path:reverse():find(PATHSEP)
+  if not s then return path end
+  return path:sub(#path - s + 1)
+end
+
+
+function common.copy(src, dst)
+  local src_stat, dst_stat = system.stat(src), system.stat(dst)
+  if not src_stat then error("can't find " .. src) end
+  if dst_stat and dst_stat.type == "dir" and src_stat.type == "file" then return common.copy(src, dst .. PATHSEP .. common.basename(src)) end
+  if dst_stat then error("path " .. dst .. " exists") end
+  local src_io, dst_io = io.open(src, "rb"), io.write(dst, "wb")
+  while true do
+    local chunk = src_io:read(16*1024)
+    if not chunk then break end
+    dst_io:write(chunk)
+  end
+end
+
+local HOME, USERDIR, CACHEDIR, JSON, repositories
+
+local Repository = {}
+function Repository.__index(self, idx) return rawget(self, idx) or Repository[idx] end
+function Repository.new(hash)
+  if not hash.remote then error("requires a remote") end
+  local self = setmetatable({ 
+    commit = hash.commit,
+    remote = hash.remote, 
+    branch = hash.branch,
+    plugins = nil,
+    local_path = CACHEDIR .. PATHSEP .. system.hash(hash.remote),
+    last_retrieval = nil 
+  }, Repository)
+  if system.stat(self.local_path) and not self.commit and not self.branch then
+    -- In the case where we don't have a branch, and don't have a commit, check for the presence of `master` and `main`.
+    if system.stat(self.local_path .. PATHSEP .. "master") then
+      self.branch = "master"
+    elseif system.stat(self.local_path .. PATHSEP .. PATHSEP .. "main") then
+      self.branch = "main"
+    end
+  end
+  self:parse_manifest()
+  return self
+end
+
+
+function Repository:parse_manifest()
+  if self.manifest then return self.manifest end
+  if system.stat(self.local_path) and system.stat(self.local_path .. PATHSEP .. (self.commit or self.branch)) then
+    self.manifest_path = self.local_path .. PATHSEP .. (self.commit or self.branch) .. PATHSEP .. "manifest.json"
+    if system.stat(self.manifest_path) then 
+      self.manifest = json.parse(io.open(manifest_path, "rb"):read("*all")) 
+      self.plugins = {}
+      for i, metadata in ipairs(self.manifest["plugins"]) do
+        table.insert(self.plugins, Plugin.new(self, metadata))
+      end
+    end
+  end
+  return self.manifest
+end
+
+
+-- in the cases where we don't have a manifest, assume generalized structure, take plugins folder, trawl through it, build manifest that way
+-- assuming each .lua file under 
+function Repository:generate_manifest()
+  
+end
+
+function Repository:add()
+  -- If neither specified then pull onto `master`, and check the main branch name, and move if necessary.
+  if not self.branch and not self.commit then 
+    local path = self.local_path .. PATHSEP .. "master"
+    common.mkdirp(path)
+    system.init(path, self.remote)
+    if not pcall(system.reset, "refs/heads/master") then
+      if pcall(system.reset, "refs/heads/main") then
+        os.rename(path, self.local_path .. PATHSEP .. "main")
+      else
+        error("Can't find master or main.")
+      end
+    end
+  else
+    local path = self.local_path .. PATHSEP .. (self.commit or self.branch)
+    common.mkdirp(path)
+    system.init(path, self.remote)
+    system.fetch(path)
+    system.reset(path, self.commit or ("refs/remotes/origin/" .. self.branch), "hard")
+    self.manifest = nil
+    self:parse_manifest()
+  end
+end
+
+
+function Repository:update()
+  if self.branch then
+    local path = self.local_path .. PATHSEP .. self.branch
+    system.fetch(path)
+    system.reset(path, "refs/remotes/origin/" .. self.branch, "hard")
+    self.manifest = nil
+    self:parse_manifest()
+  end
+end
+
+
+function Repository:remove()
+  common.rmrf(self.path)
+end
+
+
+local Plugin = { __index = function(self, idx) return rawget(self, idx) or Plugin[idx] end }
+function Plugin.new(repository, metadata)
+  return setmetatable(common.merge({
+    repository = repository,
+    tags = {},
+    remote = nil,
+    path = nil,
+    version = "1.0",
+    local_path = repository.local_path .. PATHSEP .. "repo" .. PATHSEP .. (metadata.path or metadata.name),
+    install_path = USERDIR .. PATHSEP .. "plugins" .. PATHSEP .. (metadata.path or metadata.name),
+  }, metadata), Plugin)
+end
+
+function Plugin:install()
+  common.copy(self.local_path, self.install_path)
+end
+
+
+function Plugin:uninstall()
+  common.rmrf(self.install_path)
+end
+
+
+local function get_repository(url)
+  if not url then error("requires a repository url") end
+  for i,v in ipairs(repositories) do
+    if v.url == url then return i, v end
+  end
+  return nil
+end
+
+
+local function match_version(version, pattern)
+  return not pattern or version == pattern
+end
+
+
+local function get_plugin(name, version)
+  local candidates = {}
+  for i,repo in ipairs(repositories) do
+    for j,plugin in ipairs(repo.plugins) do
+      if match_version(plugin.version, version) then
+        table.insert(candidates, plugin)
+      end
+    end
+  end
+  return table.unpack(table.sort(candidates, function (a,b) return a.version < b.version end))
+end
+
+
+local function lpm_add(url)
+  local idx, repo = get_repository(url)
+  if repo then -- if we're alreayd a repo, put this at the head of the resolution list
+    table.remove(repositories, idx)
+  else
+    repo = Repository.new(url):add()
+  end
+  table.insert(repositories, 1, repo)
+  repo:update()
+end
+
+
+local function lpm_rm(url)
+  local idx, repo = get_repository(url)
+  if not repo then error("cannot find repository " .. url) end
+  table.remove(repositories, idx)
+  repo:remove()
+end
+
+
+local function lpm_update(url)
+  local repo = url and get_repository(url)
+  for i,v in ipairs(repositories) do if not repo or v == repo then v:update() end end
+end
+
+
+local function lpm_install(name, version)
+  local plugin = get_plugin(name, version)
+  if not plugin then error("can't find plugin " .. name) end
+  plugin:install()
+end
+
+
+local function lpm_uninstall(name)
+  local plugin = get_plugin(name, version)
+  if not plugin then error("can't find plugin " .. name) end
+  if not plugin.installed then error("plugin " .. name .. " not installed") end
+  plugin:uninstall()
+end
+
+
+local function lpm_list() 
+  local result = { plugins = { } }
+  for i,repo in ipairs(repositories) do
+    if not repo.plugins then error("can't find plugins for repo " .. repo.remote .. ":" .. (repo.commit or repo.branch or "master")) end
+    for j,plugin in ipairs(repo.plugins) do
+      table.insert(result.plugins, plugin)
+    end
+  end
+  if JSON then
+    io.stdout:write(json.encode(result))
+  else
+    
+  end
+end
+
+
+local function lpm_purge()
+  common.rmrf(CACHEDIR)
+end
+
+
+local status = 0
+xpcall(function()
+  JSON = os.getenv("LPM_JSON")
+  HOME = (os.getenv("USERPROFILE") or os.getenv("HOME")):gsub(PATHSEP .. "$", "")
+  USERDIR = os.getenv("LITE_USERDIR") or (os.getenv("XDG_CONFIG_HOME") and os.getenv("XDG_CONFIG_HOME") .. PATHSEP .. "lite-xl")
+       or (HOME and (HOME .. PATHSEP .. '.config' .. PATHSEP .. 'lite-xl'))
+  CACHEDIR = os.getenv("LPM_CACHE") or USERDIR .. PATHSEP .. "lpm"
+  repositories = {}
+  repositories = { Repository.new({ remote = "https://github.com/lite-xl/lite-xl-plugins.git", branch = "master" }) }
+  if not system.stat(CACHEDIR) or not system.stat(repositories[1].local_path) then 
+    common.mkdirp(repositories[1].local_path)
+    repositories[1]:add()
+  else
+    for i, remote_hash in ipairs(system.ls(CACHEDIR)) do
+      local remote
+      for j, commit_or_branch in ipairs(system.ls(CACHEDIR .. PATHSEP .. remote_hash)) do
+        if system.stat(CACHEDIR .. PATHSEP .. remote_hash .. PATHSEP  .. commit_or_branch .. PATHSEP .. ".git" .. PATHSEP .."config") then
+          for line in io.lines(CACHEDIR .. PATHSEP .. remote_hash .. PATHSEP  .. commit_or_branch .. PATHSEP .. ".git" .. PATHSEP .."config") do
+            local s,e = line:find("url = ") 
+            if s then remote = line:sub(s+1) break end
+          end
+          if remote then
+            if #commit_or_branch == 40 and not commit_or_branch:find("[^a-z0-9]") then
+              table.insert(repositories, Repository.new({ remote = remote, commit = commit_or_branch }))
+            else
+              table.insert(repositories, Repository.new({ remote = remote, branch = commit_or_branch }))
+            end
+          end
+        end
+      end
+    end
+  end
+
+  if ARGV[2] == "add" then return lpm_add(ARGV[3]) end
+  if ARGV[2] == "rm" then  return lpm_rm(ARGV[3]) end
+  if ARGV[2] == "update" then return lpm_update(ARGV[3]) end
+  if ARGV[2] == "install" then return lpm_install(ARGV[3]) end
+  if ARGV[2] == "uninstall" then return lpm_uninstall(ARGV[3]) end
+  if ARGV[2] == "purge" then return lpm_purge(ARGV[4]) end
+  if ARGV[2] == "list" then return lpm_list() end
+  io.stderr:write([[
+Usage: lpm COMMAND
+
+LPM is a package manager for `lite-xl`, written in C (and packed-in lua).
+
+It has the following commands:
+
+lpm add <repository remote>
+lpm rm <repository remote>
+lpm update [<repository remote>]
+lpm install <plugin name>
+lpm uninstall <plugin name>
+lpm list
+]])
+end, function(err)
+  if JSON then
+    io.stderr:write(json.encode({ error = err, traceback = debug.traceback() }))
+  else
+    io.stderr:write(err .. "\n")
+    io.stderr:write(debug.traceback() .. "\n")
+  end
+  status = -1
+end)
+
+
+return status;