Do not check for valid utf8 in set text, render the invalid utf8 instead. Mmap fonts instead of loading the whole font

7 files changed, 125 insertions, 32 deletions

diff --git a/include/mgl/graphics/text.h b/include/mgl/graphics/text.h
index 2311d23..a645b0b 100644
--- a/include/mgl/graphics/text.h
+++ b/include/mgl/graphics/text.h
@@ -28,14 +28,14 @@ typedef struct {
     Note: keeps a reference to |text|. |text| needs to be valid as long as |self| is used.
     |font| and |text| may be NULL.
 */
-int mgl_text_init(mgl_text *self, mgl_font *font, const char *str, size_t str_size);
+void mgl_text_init(mgl_text *self, mgl_font *font, const char *str, size_t str_size);
 void mgl_text_deinit(mgl_text *self);
 
 /*
     Note: keeps a reference to |text|. |text| needs to be valid as long as |self| is used.
     |text| may be NULL.
 */
-int mgl_text_set_string(mgl_text *self, const char *str, size_t str_size);
+void mgl_text_set_string(mgl_text *self, const char *str, size_t str_size);
 /* |font| may be NULL */
 void mgl_text_set_font(mgl_text *self, mgl_font *font);
 void mgl_text_set_position(mgl_text *self, mgl_vec2f position);
diff --git a/include/mgl/system/fileutils.h b/include/mgl/system/fileutils.h
index 7696679..5e45cb3 100644
--- a/include/mgl/system/fileutils.h
+++ b/include/mgl/system/fileutils.h
@@ -13,8 +13,23 @@ typedef struct {
     bool null_terminated; /* false by default */
 } mgl_file_load_options;
 
+typedef struct {
+    void *data;
+    size_t size;
+    int fd;
+} mgl_memory_mapped_file;
+
+typedef struct {
+    bool readable; /* true by default */
+    bool writable; /* true by default */
+} mgl_memory_mapped_file_load_options;
+
 /* |load_options| can be null, in which case the default options are used */
 int mgl_load_file(const char *filepath, mgl_filedata *filedata, mgl_file_load_options *load_options);
 void mgl_filedata_free(mgl_filedata *self);
 
+/* |load_options| can be null, in which case the default options are used */
+int mgl_mapped_file_load(const char *filepath, mgl_memory_mapped_file *memory_mapped_file, mgl_memory_mapped_file_load_options *load_options);
+void mgl_mapped_file_unload(mgl_memory_mapped_file *memory_mapped_file);
+
 #endif /* MGL_FILEUTILS_H */
diff --git a/include/mgl/system/utf8.h b/include/mgl/system/utf8.h
index f745be7..7120f1a 100644
--- a/include/mgl/system/utf8.h
+++ b/include/mgl/system/utf8.h
@@ -5,6 +5,9 @@
 #include <stdint.h>
 #include <stdbool.h>
 
+/*
+    Returns false on failure. |decoded_codepoint| is set to |str[0]| if size > 0 and |codepoint_length| is set to 1
+*/
 bool mgl_utf8_decode(const unsigned char *str, size_t size, uint32_t *decoded_codepoint, size_t *codepoint_length);
 
 #endif /* MGL_UTF8_H */
diff --git a/src/graphics/font.c b/src/graphics/font.c
index 175c571..dfffc7e 100644
--- a/src/graphics/font.c
+++ b/src/graphics/font.c
@@ -26,16 +26,16 @@ int mgl_font_load_from_file(mgl_font *self, const char *filepath, unsigned int c
     self->packed_chars = NULL;
     self->num_packed_chars = 0;
 
-    mgl_filedata filedata;
-    if(mgl_load_file(filepath, &filedata, NULL) != 0) {
+    mgl_memory_mapped_file mapped_file;
+    if(mgl_mapped_file_load(filepath, &mapped_file, &(mgl_memory_mapped_file_load_options){ .readable = true, .writable = false }) != 0) {
         fprintf(stderr, "Error: failed to load font %s, error: mgl_load_file failed\n", filepath);
         return -1;
     }
 
     stbtt_fontinfo font;
-    if(!stbtt_InitFont(&font, filedata.data, stbtt_GetFontOffsetForIndex(filedata.data, 0))) {
+    if(!stbtt_InitFont(&font, mapped_file.data, stbtt_GetFontOffsetForIndex(mapped_file.data, 0))) {
         fprintf(stderr, "Error: failed to load font %s, error: stbtt_InitFont failed\n", filepath);
-        mgl_filedata_free(&filedata);
+        mgl_mapped_file_unload(&mapped_file);
         return -1;
     }
 
@@ -43,9 +43,7 @@ int mgl_font_load_from_file(mgl_font *self, const char *filepath, unsigned int c
     self->packed_chars = malloc(self->num_packed_chars * sizeof(stbtt_packedchar));
     if(!self->packed_chars) {
         fprintf(stderr, "Error: failed to load font %s, error: out of memory\n", filepath);
-        mgl_filedata_free(&filedata);
-        mgl_font_unload(self);
-        return -1;
+        goto error;
     }
 
     bool atlas_created = false;
@@ -62,9 +60,7 @@ int mgl_font_load_from_file(mgl_font *self, const char *filepath, unsigned int c
         unsigned char *new_atlas = realloc(self->font_atlas.atlas, self->font_atlas.width * self->font_atlas.height);
         if(!new_atlas) {
             fprintf(stderr, "Error: failed to load font %s, error: out of memory\n", filepath);
-            mgl_filedata_free(&filedata);
-            mgl_font_unload(self);
-            return -1;
+            goto error;
         }
         self->font_atlas.atlas = new_atlas;
 
@@ -72,19 +68,17 @@ int mgl_font_load_from_file(mgl_font *self, const char *filepath, unsigned int c
 
         if(!stbtt_PackBegin(&pc, self->font_atlas.atlas, self->font_atlas.width, self->font_atlas.height, self->font_atlas.width, 1, NULL)) {
             fprintf(stderr, "Error: failed to load font %s, error: stbtt_PackBegin failed\n", filepath);
-            mgl_filedata_free(&filedata);
-            mgl_font_unload(self);
-            return -1;
+            goto error;
         }
 
         stbtt_PackSetOversampling(&pc, 2, 2);
 
-        if(!stbtt_PackFontRange(&pc, filedata.data, 0, self->character_size, 0, self->num_packed_chars, self->packed_chars)) {
+        if(!stbtt_PackFontRange(&pc, mapped_file.data, 0, self->character_size, 0, self->num_packed_chars, self->packed_chars)) {
             stbtt_PackEnd(&pc);
             continue;
         }
 
-        /*if(!stbtt_PackFontRange(&pc, filedata.data, 0, self->character_size, 0x00004E00, self->num_packed_chars, self->packed_chars)) {
+        /*if(!stbtt_PackFontRange(&pc, mapped_file.data, 0, self->character_size, 0x00004E00, self->num_packed_chars, self->packed_chars)) {
             stbtt_PackEnd(&pc);
             continue;
         }*/
@@ -96,22 +90,23 @@ int mgl_font_load_from_file(mgl_font *self, const char *filepath, unsigned int c
 
     if(!atlas_created) {
         fprintf(stderr, "Error: failed to load font %s, error: failed to create atlas\n", filepath);
-        mgl_filedata_free(&filedata);
-        mgl_font_unload(self);
-        return -1;
+        goto error;
     }
 
     if(mgl_texture_load_from_memory(&self->texture, self->font_atlas.atlas, self->font_atlas.width, self->font_atlas.height, MGL_IMAGE_FORMAT_ALPHA, NULL) != 0) {
         fprintf(stderr, "Error: failed to load font %s, error: mgl_texture_load_from_memory failed\n", filepath);
-        mgl_filedata_free(&filedata);
-        mgl_font_unload(self);
-        return -1;
+        goto error;
     }
 
     /* TODO: Use stbtt_GetCodepointSDF */
     
-    mgl_filedata_free(&filedata);
+    mgl_mapped_file_unload(&mapped_file);
     return 0;
+
+    error:
+    mgl_mapped_file_unload(&mapped_file);
+    mgl_font_unload(self);
+    return -1;
 }
 
 void mgl_font_unload(mgl_font *self) {
diff --git a/src/graphics/text.c b/src/graphics/text.c
index 28840ce..d330dc0 100644
--- a/src/graphics/text.c
+++ b/src/graphics/text.c
@@ -47,13 +47,13 @@ static mgl_vec2f mgl_text_calculate_bounds(mgl_text *self) {
     return bounds;
 }
 
-int mgl_text_init(mgl_text *self, mgl_font *font, const char *str, size_t str_size) {
+void mgl_text_init(mgl_text *self, mgl_font *font, const char *str, size_t str_size) {
     self->font = font;
     self->color = (mgl_color){ 255, 255, 255, 255 };
     self->position = (mgl_vec2f){ 0.0f, 0.0f };
     self->text = NULL;
     self->text_size = 0;
-    return mgl_text_set_string(self, str, str_size);
+    mgl_text_set_string(self, str, str_size);
 }
 
 void mgl_text_deinit(mgl_text *self) {
@@ -64,14 +64,13 @@ void mgl_text_deinit(mgl_text *self) {
     self->bounds = (mgl_vec2f){ 0.0f, 0.0f };
 }
 
-int mgl_text_set_string(mgl_text *self, const char *str, size_t str_size) {
+void mgl_text_set_string(mgl_text *self, const char *str, size_t str_size) {
     self->text = str;
     self->text_size = str_size;
     if(self->text && self->text_size > 0 && self->font)
         self->bounds = mgl_text_calculate_bounds(self);
     else
         self->bounds = (mgl_vec2f){ 0.0f, 0.0f };
-    return 0;
 }
 
 void mgl_text_set_font(mgl_text *self, mgl_font *font) {
diff --git a/src/system/fileutils.c b/src/system/fileutils.c
index dc8eaca..86d176a 100644
--- a/src/system/fileutils.c
+++ b/src/system/fileutils.c
@@ -1,5 +1,6 @@
 #include "../../include/mgl/system/fileutils.h"
 #include <sys/stat.h>
+#include <sys/mman.h>
 #include <fcntl.h>
 #include <unistd.h>
 #include <stdlib.h>
@@ -49,3 +50,71 @@ void mgl_filedata_free(mgl_filedata *self) {
     self->data = NULL;
     self->size = 0;
 }
+
+static int load_options_to_open_flag(mgl_memory_mapped_file_load_options *load_options) {
+    const bool readable = load_options ? load_options->readable : true;
+    const bool writable = load_options ? load_options->writable : true;
+
+    int open_flag = 0;
+    if(readable && writable)
+        open_flag = O_RDWR;
+    else if(readable)
+        open_flag = O_RDONLY;
+    else if(writable)
+        open_flag = O_WRONLY;
+
+    return open_flag;
+}
+
+static int load_options_to_mmap_prot_flag(mgl_memory_mapped_file_load_options *load_options) {
+    const bool readable = load_options ? load_options->readable : true;
+    const bool writable = load_options ? load_options->writable : true;
+
+    int prot_flag = 0;
+    if(readable)
+        prot_flag |= PROT_READ;
+    if(writable)
+        prot_flag |= PROT_WRITE;
+
+    return prot_flag;
+}
+
+int mgl_mapped_file_load(const char *filepath, mgl_memory_mapped_file *memory_mapped_file, mgl_memory_mapped_file_load_options *load_options) {
+    memory_mapped_file->data = NULL;
+    memory_mapped_file->size = 0;
+    memory_mapped_file->fd = -1;
+
+    int fd = open(filepath, load_options_to_open_flag(load_options));
+    if(fd == -1)
+        return -1;
+
+    struct stat st;
+    if(fstat(fd, &st) == -1) {
+        close(fd);
+        return -1;
+    }
+
+    void *mapped = mmap(0, st.st_size, load_options_to_mmap_prot_flag(load_options), MAP_SHARED, fd, 0);
+    if(mapped == MAP_FAILED) {
+        close(fd);
+        return -1;
+    }
+
+    memory_mapped_file->data = mapped;
+    memory_mapped_file->size = st.st_size;
+    memory_mapped_file->fd = fd;
+    return 0;
+}
+
+void mgl_mapped_file_unload(mgl_memory_mapped_file *memory_mapped_file) {
+    if(memory_mapped_file->data != MAP_FAILED && memory_mapped_file->data != NULL) {
+        munmap(memory_mapped_file->data, memory_mapped_file->size);
+        memory_mapped_file->data = NULL;
+    }
+    memory_mapped_file->size = 0;
+
+    if(memory_mapped_file->fd != -1) {
+        close(memory_mapped_file->fd);
+        memory_mapped_file->fd = -1;
+    }
+}
diff --git a/src/system/utf8.c b/src/system/utf8.c
index 35b0f2f..201fedf 100644
--- a/src/system/utf8.c
+++ b/src/system/utf8.c
@@ -20,19 +20,31 @@ static inline bool utf8_get_codepoint_length(unsigned char b, size_t *codepoint_
 
 /* TODO: Optimize (remove branching, etc) */
 bool mgl_utf8_decode(const unsigned char *str, size_t size, uint32_t *decoded_codepoint, size_t *codepoint_length) {
-    if(size == 0)
+    if(size == 0) {
+        *decoded_codepoint = 0;
+        *codepoint_length = 0;
         return false;
+    }
 
     size_t clen;
-    if(!utf8_get_codepoint_length(str[0], &clen))
+    if(!utf8_get_codepoint_length(str[0], &clen)) {
+        *decoded_codepoint = str[0];
+        *codepoint_length = 1;
         return false;
+    }
 
-    if(size < clen)
+    if(size < clen) {
+        *decoded_codepoint = str[0];
+        *codepoint_length = 1;
         return false;
+    }
 
     for(size_t i = 1; i < clen; ++i) {
-        if((str[i] & 0xC0) != 0x80)
+        if((str[i] & 0xC0) != 0x80) {
+            *decoded_codepoint = str[0];
+            *codepoint_length = 1;
             return false;
+        }
     }
 
     uint32_t codepoint;