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-rw-r--r--scripts/gendispatch.lua313
1 files changed, 313 insertions, 0 deletions
diff --git a/scripts/gendispatch.lua b/scripts/gendispatch.lua
new file mode 100644
index 0000000000..54bfdab45b
--- /dev/null
+++ b/scripts/gendispatch.lua
@@ -0,0 +1,313 @@
+lpeg = require('lpeg')
+mpack = require('mpack')
+
+-- lpeg grammar for building api metadata from a set of header files. It
+-- ignores comments and preprocessor commands and parses a very small subset
+-- of C prototypes with a limited set of types
+P, R, S = lpeg.P, lpeg.R, lpeg.S
+C, Ct, Cc, Cg = lpeg.C, lpeg.Ct, lpeg.Cc, lpeg.Cg
+
+any = P(1) -- (consume one character)
+letter = R('az', 'AZ') + S('_$')
+alpha = letter + R('09')
+nl = P('\r\n') + P('\n')
+not_nl = any - nl
+ws = S(' \t') + nl
+fill = ws ^ 0
+c_comment = P('//') * (not_nl ^ 0)
+c_preproc = P('#') * (not_nl ^ 0)
+typed_container =
+ (P('ArrayOf(') + P('DictionaryOf(')) * ((any - P(')')) ^ 1) * P(')')
+c_id = (
+ typed_container +
+ (letter * (alpha ^ 0))
+)
+c_void = P('void')
+c_param_type = (
+ ((P('Error') * fill * P('*') * fill) * Cc('error')) +
+ (C(c_id) * (ws ^ 1))
+ )
+c_type = (C(c_void) * (ws ^ 1)) + c_param_type
+c_param = Ct(c_param_type * C(c_id))
+c_param_list = c_param * (fill * (P(',') * fill * c_param) ^ 0)
+c_params = Ct(c_void + c_param_list)
+c_proto = Ct(
+ Cg(c_type, 'return_type') * Cg(c_id, 'name') *
+ fill * P('(') * fill * Cg(c_params, 'parameters') * fill * P(')') *
+ Cg(Cc(false), 'async') *
+ (fill * Cg((P('FUNC_API_ASYNC') * Cc(true)), 'async') ^ -1) *
+ (fill * Cg((P('FUNC_API_NOEXPORT') * Cc(true)), 'noexport') ^ -1) *
+ fill * P(';')
+ )
+grammar = Ct((c_proto + c_comment + c_preproc + ws) ^ 1)
+
+-- we need at least 2 arguments since the last one is the output file
+assert(#arg >= 1)
+functions = {}
+
+-- names of all headers relative to the source root (for inclusion in the
+-- generated file)
+headers = {}
+-- output file(dispatch function + metadata serialized with msgpack)
+outputf = arg[#arg]
+
+-- read each input file, parse and append to the api metadata
+for i = 1, #arg - 1 do
+ local full_path = arg[i]
+ local parts = {}
+ for part in string.gmatch(full_path, '[^/]+') do
+ parts[#parts + 1] = part
+ end
+ headers[#headers + 1] = parts[#parts - 1]..'/'..parts[#parts]
+
+ local input = io.open(full_path, 'rb')
+ local tmp = grammar:match(input:read('*all'))
+ for i = 1, #tmp do
+ local fn = tmp[i]
+ if not fn.noexport then
+ functions[#functions + 1] = tmp[i]
+ if #fn.parameters ~= 0 and fn.parameters[1][2] == 'channel_id' then
+ -- this function should receive the channel id
+ fn.receives_channel_id = true
+ -- remove the parameter since it won't be passed by the api client
+ table.remove(fn.parameters, 1)
+ end
+ if #fn.parameters ~= 0 and fn.parameters[#fn.parameters][1] == 'error' then
+ -- function can fail if the last parameter type is 'Error'
+ fn.can_fail = true
+ -- remove the error parameter, msgpack has it's own special field
+ -- for specifying errors
+ fn.parameters[#fn.parameters] = nil
+ end
+ end
+ end
+ input:close()
+end
+
+
+-- start building the output
+output = io.open(outputf, 'wb')
+
+output:write([[
+#include <inttypes.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <assert.h>
+#include <msgpack.h>
+
+#include "nvim/map.h"
+#include "nvim/log.h"
+#include "nvim/vim.h"
+#include "nvim/msgpack_rpc/helpers.h"
+#include "nvim/api/private/dispatch.h"
+#include "nvim/api/private/helpers.h"
+#include "nvim/api/private/defs.h"
+]])
+
+for i = 1, #headers do
+ if headers[i]:sub(-12) ~= '.generated.h' then
+ output:write('\n#include "nvim/'..headers[i]..'"')
+ end
+end
+
+output:write([[
+
+
+static const uint8_t msgpack_metadata[] = {
+
+]])
+-- serialize the API metadata using msgpack and embed into the resulting
+-- binary for easy querying by clients
+packed = mpack.pack(functions)
+for i = 1, #packed do
+ output:write(string.byte(packed, i)..', ')
+ if i % 10 == 0 then
+ output:write('\n ')
+ end
+end
+output:write([[
+};
+
+void msgpack_rpc_init_function_metadata(Dictionary *metadata)
+{
+ msgpack_unpacked unpacked;
+ msgpack_unpacked_init(&unpacked);
+ if (msgpack_unpack_next(&unpacked,
+ (const char *)msgpack_metadata,
+ sizeof(msgpack_metadata),
+ NULL) != MSGPACK_UNPACK_SUCCESS) {
+ abort();
+ }
+ Object functions;
+ msgpack_rpc_to_object(&unpacked.data, &functions);
+ msgpack_unpacked_destroy(&unpacked);
+ PUT(*metadata, "functions", functions);
+}
+
+]])
+
+local function real_type(type)
+ local rv = type
+ if typed_container:match(rv) then
+ if rv:match('Array') then
+ rv = 'Array'
+ else
+ rv = 'Dictionary'
+ end
+ end
+ return rv
+end
+
+-- start the handler functions. Visit each function metadata to build the
+-- handler function with code generated for validating arguments and calling to
+-- the real API.
+for i = 1, #functions do
+ local fn = functions[i]
+ local args = {}
+
+ output:write('static Object handle_'..fn.name..'(uint64_t channel_id, uint64_t request_id, Array args, Error *error)')
+ output:write('\n{')
+ output:write('\n Object ret = NIL;')
+ -- Declare/initialize variables that will hold converted arguments
+ for j = 1, #fn.parameters do
+ local param = fn.parameters[j]
+ local converted = 'arg_'..j
+ output:write('\n '..param[1]..' '..converted..' api_init_'..string.lower(real_type(param[1]))..';')
+ end
+ output:write('\n')
+ output:write('\n if (args.size != '..#fn.parameters..') {')
+ output:write('\n snprintf(error->msg, sizeof(error->msg), "Wrong number of arguments: expecting '..#fn.parameters..' but got %zu", args.size);')
+ output:write('\n error->set = true;')
+ output:write('\n goto cleanup;')
+ output:write('\n }\n')
+
+ -- Validation/conversion for each argument
+ for j = 1, #fn.parameters do
+ local converted, convert_arg, param, arg
+ param = fn.parameters[j]
+ converted = 'arg_'..j
+ local rt = real_type(param[1])
+ if rt ~= 'Object' then
+ output:write('\n if (args.items['..(j - 1)..'].type == kObjectType'..rt..') {')
+ output:write('\n '..converted..' = args.items['..(j - 1)..'].data.'..rt:lower()..';')
+ if rt:match('^Buffer$') or rt:match('^Window$') or rt:match('^Tabpage$') or rt:match('^Boolean$') then
+ -- accept positive integers for Buffers, Windows and Tabpages
+ output:write('\n } else if (args.items['..(j - 1)..'].type == kObjectTypeInteger && args.items['..(j - 1)..'].data.integer > 0) {')
+ output:write('\n '..converted..' = (unsigned)args.items['..(j - 1)..'].data.integer;')
+ end
+ output:write('\n } else {')
+ output:write('\n snprintf(error->msg, sizeof(error->msg), "Wrong type for argument '..j..', expecting '..param[1]..'");')
+ output:write('\n error->set = true;')
+ output:write('\n goto cleanup;')
+ output:write('\n }\n')
+ else
+ output:write('\n '..converted..' = args.items['..(j - 1)..'];\n')
+ end
+
+ args[#args + 1] = converted
+ end
+
+ -- function call
+ local call_args = table.concat(args, ', ')
+ output:write('\n ')
+ if fn.return_type ~= 'void' then
+ -- has a return value, prefix the call with a declaration
+ output:write(fn.return_type..' rv = ')
+ end
+
+ -- write the function name and the opening parenthesis
+ output:write(fn.name..'(')
+
+ if fn.receives_channel_id then
+ -- if the function receives the channel id, pass it as first argument
+ if #args > 0 or fn.can_fail then
+ output:write('channel_id, '..call_args)
+ else
+ output:write('channel_id')
+ end
+ else
+ output:write(call_args)
+ end
+
+ if fn.can_fail then
+ -- if the function can fail, also pass a pointer to the local error object
+ if #args > 0 then
+ output:write(', error);\n')
+ else
+ output:write('error);\n')
+ end
+ -- and check for the error
+ output:write('\n if (error->set) {')
+ output:write('\n goto cleanup;')
+ output:write('\n }\n')
+ else
+ output:write(');\n')
+ end
+
+ if fn.return_type ~= 'void' then
+ output:write('\n ret = '..string.upper(real_type(fn.return_type))..'_OBJ(rv);')
+ end
+ -- Now generate the cleanup label for freeing memory allocated for the
+ -- arguments
+ output:write('\n\ncleanup:');
+
+ for j = 1, #fn.parameters do
+ local param = fn.parameters[j]
+ output:write('\n api_free_'..string.lower(real_type(param[1]))..'(arg_'..j..');')
+ end
+ output:write('\n return ret;\n}\n\n');
+end
+
+-- Generate a function that initializes method names with handler functions
+output:write([[
+static Map(String, MsgpackRpcRequestHandler) *methods = NULL;
+
+void msgpack_rpc_add_method_handler(String method, MsgpackRpcRequestHandler handler)
+{
+ map_put(String, MsgpackRpcRequestHandler)(methods, method, handler);
+}
+
+void msgpack_rpc_init_method_table(void)
+{
+ methods = map_new(String, MsgpackRpcRequestHandler)();
+
+]])
+
+-- Keep track of the maximum method name length in order to avoid walking
+-- strings longer than that when searching for a method handler
+local max_fname_len = 0
+for i = 1, #functions do
+ local fn = functions[i]
+ output:write(' msgpack_rpc_add_method_handler('..
+ '(String) {.data = "'..fn.name..'", '..
+ '.size = sizeof("'..fn.name..'") - 1}, '..
+ '(MsgpackRpcRequestHandler) {.fn = handle_'.. fn.name..
+ ', .async = '..tostring(fn.async)..'});\n')
+
+ if #fn.name > max_fname_len then
+ max_fname_len = #fn.name
+ end
+end
+
+output:write('\n}\n\n')
+
+output:write([[
+MsgpackRpcRequestHandler msgpack_rpc_get_handler_for(const char *name,
+ size_t name_len)
+{
+ String m = {
+ .data=(char *)name,
+ .size=MIN(name_len, ]]..max_fname_len..[[)
+ };
+ MsgpackRpcRequestHandler rv =
+ map_get(String, MsgpackRpcRequestHandler)(methods, m);
+
+ if (!rv.fn) {
+ rv.fn = msgpack_rpc_handle_missing_method;
+ }
+
+ return rv;
+}
+]])
+
+output:close()
generated by cgit (git 2.34.1) at 2025-04-29 05:47:31 +0000