From b644d4620ac380212918f52da6e74d2f03babcb3 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Thu, 28 Sep 2017 16:29:12 +0530
Subject: [PATCH] OS X does not support write() with shared memory

---
 kitty/graphics.c        | 18 +++++++++++++-----
 kitty_tests/graphics.py |  4 +---
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/kitty/graphics.c b/kitty/graphics.c
index 14c3e652a..478141260 100644
--- a/kitty/graphics.c
+++ b/kitty/graphics.c
@@ -456,12 +456,20 @@ W(image_for_client_id) {
     return image_as_dict(img);
 }
 
-W(shm_open) {
-    char *name;
-    PA("s", &name);
+W(shm_write) {
+    const char *name, *data;
+    Py_ssize_t sz;
+    PA("ss#", &name, &data, &sz);
     int fd = shm_open(name, O_CREAT |  O_RDWR, S_IROTH | S_IRUSR | S_IRGRP | S_IWUSR);
     if (fd == -1) { PyErr_SetFromErrnoWithFilename(PyExc_OSError, name); return NULL; }
-    return PyLong_FromLong(fd);
+    int ret = ftruncate(fd, sz);
+    if (ret != 0) { PyErr_SetFromErrnoWithFilename(PyExc_OSError, name); return NULL; }
+    void *addr = mmap(0, sz, PROT_WRITE, MAP_SHARED, fd, 0);
+    if (addr == MAP_FAILED) { PyErr_SetFromErrnoWithFilename(PyExc_OSError, name); return NULL; }
+    memcpy(addr, data, sz);
+    if (munmap(addr, sz) != 0) { PyErr_SetFromErrnoWithFilename(PyExc_OSError, name); return NULL; }
+    close(fd);
+    Py_RETURN_NONE;
 }
 
 W(shm_unlink) {
@@ -476,7 +484,7 @@ W(shm_unlink) {
 
 static PyMethodDef methods[] = {
     M(image_for_client_id, METH_O),
-    M(shm_open, METH_VARARGS),
+    M(shm_write, METH_VARARGS),
     M(shm_unlink, METH_VARARGS),
     {NULL}  /* Sentinel */
 };
diff --git a/kitty_tests/graphics.py b/kitty_tests/graphics.py
index 49f54c01c..d684ebbd7 100644
--- a/kitty_tests/graphics.py
+++ b/kitty_tests/graphics.py
@@ -89,8 +89,6 @@ class TestGraphics(BaseTest):
 
         # Test loading from POSIX SHM
         name = '/kitty-test-shm'
-        fd = g.shm_open(name)
-        f = os.fdopen(fd, 'wb')
-        f.write(random_data), f.flush(), f.close()
+        g.shm_write(name, random_data)
         sl(name, s=24, v=32, t='s', expecting_data=random_data)
         self.assertRaises(FileNotFoundError, g.shm_unlink, name)  # check that file was deleted