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authorPhilipp Stephani <phst@google.com>2019-04-18 17:42:45 +0200
committerPhilipp Stephani <phst@google.com>2019-04-24 11:33:52 +0200
commitbffceab6339fb4042588b893ef754c6264379e75 (patch)
tree03747b5cb5275a24418aa9fb421977eb6c0ee063 /src/emacs-module.c
parent5ae407aad4f2564fae7ddce077eb01aa8efa37fb (diff)
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Add conversions to and from struct timespec to module interface.
Time values are a fundamental data type, and such conversions are hard to implement within modules because of the various forms of time values in Emacs Lisp. Adding dedicated conversion functions can significantly simplify module code dealing with times. This approach uses nanosecond precision. While Emacs in theory has support for higher-precision time values, in practice most languages and standards, such as POSIX, C, Java, and Go, have settled on nanosecond-precision integers to represent time. * src/emacs-module.h.in: Add header for struct timespec. * src/module-env-27.h: Add module functions for time conversion. * src/emacs-module.c (module_extract_time, module_make_time): New functions. (initialize_environment): Use them. * test/data/emacs-module/mod-test.c (Fmod_test_add_nanosecond): New test function. (emacs_module_init): Define it. * test/src/emacs-module-tests.el (mod-test-add-nanosecond/valid) (mod-test-add-nanosecond/nil, mod-test-add-nanosecond/invalid): New unit tests. * doc/lispref/internals.texi (Module Values): Document time conversion functions.
Diffstat (limited to 'src/emacs-module.c')
-rw-r--r--src/emacs-module.c17
1 files changed, 17 insertions, 0 deletions
diff --git a/src/emacs-module.c b/src/emacs-module.c
index b812fdc2df4..e46af30ce84 100644
--- a/src/emacs-module.c
+++ b/src/emacs-module.c
@@ -77,6 +77,7 @@ To add a new module function, proceed as follows:
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
+#include <time.h>
#include "lisp.h"
#include "dynlib.h"
@@ -737,6 +738,20 @@ module_process_input (emacs_env *env)
return emacs_process_input_continue;
}
+static struct timespec
+module_extract_time (emacs_env *env, emacs_value value)
+{
+ MODULE_FUNCTION_BEGIN ((struct timespec) {0});
+ return lisp_time_argument (value_to_lisp (value));
+}
+
+static emacs_value
+module_make_time (emacs_env *env, struct timespec time)
+{
+ MODULE_FUNCTION_BEGIN (NULL);
+ return lisp_to_value (env, make_lisp_time (time));
+}
+
/* Subroutines. */
@@ -1140,6 +1155,8 @@ initialize_environment (emacs_env *env, struct emacs_env_private *priv)
env->vec_size = module_vec_size;
env->should_quit = module_should_quit;
env->process_input = module_process_input;
+ env->extract_time = module_extract_time;
+ env->make_time = module_make_time;
Vmodule_environments = Fcons (make_mint_ptr (env), Vmodule_environments);
return env;
}