Everywhere: Give stbtt its own 32MB static memory pool

At boot time, we preallocate 32MB of RAM to reuse for all malloc()
requests by stbtt_RenderText(), which should be more than enough for the
primary use case (browsing web pages).

System/FFI/TrueType.HC

@@ -0,0 +1,31 @@
+U64 stbtt_heap = MAlloc(1048576 * 32);
+U64 stbtt_pos = 0;
+
+U64 @stbtt_malloc(I64 size)
+{
+    //"stbtt_malloc(%d)\n", size;
+    U64 ptr = stbtt_heap + stbtt_pos;
+    stbtt_pos += size;
+    return ptr;
+}
+
+U0 @stbtt_free(U8* ptr)
+{
+    //"stbtt_free(0x%08x)\n", ptr;
+}
+
+U0 _Z15truetype_malloci()
+{
+    PUSH_SYSV_REGS
+    GET_SYSV_ARGS
+    @stbtt_malloc(p0);
+    POP_SYSV_REGS
+}
+
+U0 _Z13truetype_freePv()
+{
+    PUSH_SYSV_REGS
+    GET_SYSV_ARGS
+    @stbtt_free(p0);
+    POP_SYSV_REGS
+}

System/Libraries/Graphics2D.HC

@@ -1206,7 +1206,7 @@ I64 @get_truetype_baseline(U8* font_name, I64 size)
     dc->width -= 16;
     dc->height -= size / 4;
     res = Y2Pos(dc);
-    DCDel(dc);
+    Free(dc);
     return res;
 }
 
@@ -1232,7 +1232,7 @@ U0 Text2D(Context2D* ctx, U8* font_name, I64 x, I64 y, I64 size, U32 color, U8*
     }
     BlendRect2D(text_ctx, ctx);
     DelContext2D(text_ctx);
-    DCDel(dc);
+    Free(dc);
 }
 
 Context2D* FastBoxBlur2D(Context2D* img, I64 radius)

System/MakeSystem.HC

@@ -23,6 +23,7 @@ WinToTop(adam_task);
 #include "FFI/LibC";
 #include "FFI/New";
 #include "FFI/ELF64";
+#include "FFI/TrueType";
 
 // stb_image library
 #include "Utilities/Image";

System/Utilities/TrueType.HC

@@ -44,6 +44,7 @@ U8* @stbtt_RenderText(stbtt_fontinfo* info, I32 b_w, I32 b_h, I32 l_h, I32* word
     U64 reg R8 r8 = word;
     U64 reg R9 r9 = advance;
     no_warn rdi, rsi, rdx, rcx, r8, r9;
+    stbtt_pos = 0;
     asm {
         MOV RAX, STBTT_RENDERTEXT
         CALL RAX

scripts/build-all

@@ -107,7 +107,7 @@ def build_image():
 def build_truetype():
     print("build-all: build-truetype")
     build_specific_options = '-Wl,--section-start=.text=0x1104000 -Wl,--section-start=.plt=0x1102020 -no-pie'
-    res = os.system('cd ' + project_path + '&& cd src/truetype && gcc -o ../../build/bin/truetype ' + build_specific_options + ' -O0 -mno-mmx -mno-red-zone truetype.c ../openlibm/libopenlibm.a')
+    res = os.system('cd ' + project_path + '&& cd src/truetype && gcc -o ../../build/bin/truetype ' + build_specific_options + ' -O0 -mno-mmx -mno-red-zone truetype.c ../../build/lib/libtemple.so ../openlibm/libopenlibm.a')
     if res:
         raise ValueError("build-all: step 'build-image' failed, error code " + str(res))
 
@@ -257,8 +257,8 @@ def build_all():
         refresh_build_path()
         build_image()
         build_openlibm()
-        build_truetype()
         build_libtemple()
+        build_truetype()
         build_tlse()
         transpile_net_to_sepples()
         build_net()

src/libtemple/libtemple.cpp

@@ -74,4 +74,8 @@ long time_jiffies() { return 0; }
 
 long time_now() { return 0; }
 
-void time_sleep(long duration) { }
+void time_sleep(long duration) { }
+
+void* truetype_malloc(int size) { return 0; }
+
+void truetype_free(void* ptr) { }

src/truetype/stb_truetype.h

@@ -468,8 +468,8 @@ int main(int arg, char **argv)
    // #define your own functions "STBTT_malloc" / "STBTT_free" to avoid malloc.h
    #ifndef STBTT_malloc
    #include <stdlib.h>
-   #define STBTT_malloc(x,u)  ((void)(u),malloc(x))
-   #define STBTT_free(x,u)    ((void)(u),free(x))
+   #define STBTT_malloc(x,u)  ((void)(u),_Z15truetype_malloci(x))
+   #define STBTT_free(x,u)    ((void)(u),_Z13truetype_freePv(x))
    #endif
 
    #ifndef STBTT_assert

src/truetype/truetype.c

@@ -1,3 +1,6 @@
+void* _Z15truetype_malloci(int size);
+void _Z13truetype_freePv(void* ptr);
+
 #define STB_TRUETYPE_IMPLEMENTATION
 #include "stb_truetype.h"
 
@@ -5,7 +8,8 @@ unsigned char* stbtt_RenderText(stbtt_fontinfo* info, int b_w, int b_h, int l_h,
 {
     // https://github.com/justinmeiners/stb-truetype-example
     /* create a bitmap for the phrase */
-    unsigned char* bitmap = calloc(b_w * b_h, sizeof(unsigned char));
+    unsigned char* bitmap = STBTT_malloc(b_w * b_h, sizeof(unsigned char));
+    memset(bitmap, 0, b_w * b_h);
 
     /* calculate font scaling */
     float scale = stbtt_ScaleForPixelHeight(info, l_h);