Review fixes: GL 4.3 on non-Apple, size 0 defaults, no nested app-run

Message

From the adversarial review of the branch:

Request GL 4.3 core on Linux and Windows, 4.1 on macOS, which is what sokol_app asked for (sokol_app.h:3520-3527); sokol_gfx gates compute and texture views on the reported version, so a strict driver would have lost them silently under a 4.1 request. The comment said 4.1 was sokol's choice; it was not.
(app-run ... 0 0) opens the 640x480 default, as sokol_app did, instead of raising GLFW_INVALID_VALUE.
app-run refuses to nest: a second call from inside a callback used to free the outer loop's state under it.
A Scheme error in a frame sets quit-requested? too, so a cleanup callback sees #t as it did under sokol_app.
The frame clock restarts after the init callback; a long asset load is no longer frame 1's dt.
dl-search says so on stderr when there is no underlying dlopen (a static link), and the library record lists only the files every target compiles, with a comment on why.

Changed

 package.sgl          |  8 +++++---
 src/c/app.c          | 26 +++++++++++++++++++++-----
 src/c/dl-search.c    |  7 ++++++-
 src/c/sokol-compat.c |  3 +++
 4 files changed, 35 insertions(+), 9 deletions(-)

Diff

package.sglmodified

@@ -150,9 +150,11 @@

150

libraries: (list

151

(library

152

name: 'sigil-app

−153

;; The platform-independent files; the build task adds the GLFW

−154

;; backend files for the config's target OS.

−155

c-sources: '("src/c/app.c" "src/c/sokol-compat.c" "src/c/dl-search.c")

+153

;; sigil-build reads this list only as a "has native code" test and

+154

;; for the include dirs; the build task below compiles the real,

+155

;; target-dependent list (these two plus dl-search.c on Linux plus

+156

;; the GLFW backend files). Keep it to files every target compiles.

+157

c-sources: '("src/c/app.c" "src/c/sokol-compat.c")

158

c-include-dirs: '("vendor/glfw/include" "vendor/sokol" "src/c")

159

native-init: "sigil__init_sigil_app_module"

160

;; Platform linker flags.

src/c/app.cmodified

@@ -149,6 +149,7 @@ static void check_vm_error(const char *context)

149

if (err) {

150

fprintf(stderr, "Scheme error in %s: %s\n", context, err);

151

sigil_error_clear(g_app->vm);

+152

g_app->quit_requested = true;

153

if (g_app->window) glfwSetWindowShouldClose(g_app->window, GLFW_TRUE);

154

}

155

}

@@ -303,12 +304,18 @@ static bool run_main_loop(const char *title, int width, int height)

304

return false;

305

}

306

−306

/* GL 4.1 core, the profile sokol_app asked for (and the newest macOS

−307

* offers). Forward-compat is required by macOS for core profiles and

−308

* harmless elsewhere. Depth 24 / stencil 8 are GLFW's defaults and

−309

* match the sokol_app swapchain the graphics layer expects. */

+307

/* The GL core profile sokol_app asked for: 4.3 on Linux and Windows, 4.1

+308

* on macOS (the newest it offers); sokol_gfx gates a few features on the

+309

* reported version, and Mesa and NVIDIA hand back the highest core

+310

* version either way. Forward-compat as sokol_app set it too (required

+311

* on macOS). Depth 24 / stencil 8 are GLFW's defaults and match the

+312

* sokol_app swapchain the graphics layer expects. */

313

glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);

+314

#if defined(__APPLE__)

315

glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 1);

+316

#else

+317

glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);

+318

#endif

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glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);

320

glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GLFW_TRUE);

321

glfwWindowHint(GLFW_SCALE_FRAMEBUFFER, GLFW_TRUE);

@@ -362,7 +369,9 @@ static bool run_main_loop(const char *title, int width, int height)

369

check_vm_error("init");

370

}

371

−365

/* frames */

+372

/* frames; the clock restarts after init so a long asset load is not

+373

* frame 1's dt (sokol_app handed the load time to the first frame). */

+374

g_app->last_time = glfwGetTime();

375

while (!glfwWindowShouldClose(window)) {

376

glfwPollEvents();

377

@@ -417,6 +426,10 @@ static Value native_app_run(SigilVM *vm, int argc, Value *args)

426

427

/* Initialize app state */

428

sigil_app_state_init(vm);

+429

if (g_app->window) {

+430

sigil__vm_error(vm, SIGIL_ERR_RUNTIME, "app-run: already running; app-run does not nest");

+431

return SIGIL_UNDEFINED;

+432

}

433

434

/* Store callbacks */

435

g_app->init_callback = args[0];

@@ -438,6 +451,9 @@ static Value native_app_run(SigilVM *vm, int argc, Value *args)

451

if (argc > 5 && sigil_is_fixnum(args[5])) {

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height = (int)sigil_as_fixnum(args[5]);

453

}

+454

/* 0 (or less) means the default, as with sokol_app. */

+455

if (width <= 0) width = 640;

+456

if (height <= 0) height = 480;

457

458

bool ran = run_main_loop(title, width, height);

459

src/c/dl-search.cmodified

@@ -98,7 +98,12 @@ static void *try_under(sigil_dlopen_fn real, const char *base, const char *suffi

void *dlopen(const char *name, int flags)

{

100

sigil_dlopen_fn real = real_dlopen();

−101

if (!real) return NULL;

+101

if (!real) {

+102

/* No next dlopen: only a fully static link gets here; say so, since

+103

* GLFW then reports the library as missing. */

+104

fprintf(stderr, "sigil-app: dlopen(%s): no underlying dlopen (static link?)\n", name ? name : "(null)");

+105

return NULL;

+106

}

107

108

void *h = real(name, flags);

109

if (h || !name || strchr(name, '/')) return h;

src/c/sokol-compat.cmodified

@@ -18,6 +18,9 @@

#include "app-internal.h"

#include <string.h>

+21

/* Order is load-bearing: sokol_log.h with its IMPL defines SOKOL_API_IMPL,

+22

* which the sapp_* definitions below use; sokol_app.h then contributes

+23

* declarations only. */

#define SOKOL_LOG_IMPL

#include "sokol_log.h"