1 /*
2   SDL_image:  An example image loading library for use with SDL
3   Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
4 
5   This software is provided 'as-is', without any express or implied
6   warranty.  In no event will the authors be held liable for any damages
7   arising from the use of this software.
8 
9   Permission is granted to anyone to use this software for any purpose,
10   including commercial applications, and to alter it and redistribute it
11   freely, subject to the following restrictions:
12 
13   1. The origin of this software must not be misrepresented; you must not
14      claim that you wrote the original software. If you use this software
15      in a product, an acknowledgment in the product documentation would be
16      appreciated but is not required.
17   2. Altered source versions must be plainly marked as such, and must not be
18      misrepresented as being the original software.
19   3. This notice may not be removed or altered from any source distribution.
20 */
21 
22 /* A simple library to load images of various formats as SDL surfaces */
23 
24 #include "SDL_image.h"
25 
26 #ifdef __EMSCRIPTEN__
27 #include <emscripten/emscripten.h>
28 #endif
29 
30 #define ARRAYSIZE(a) (sizeof(a) / sizeof((a)[0]))
31 
32 /* Table of image detection and loading functions */
33 static struct {
34     const char *type;
35     int (SDLCALL *is)(SDL_RWops *src);
36     SDL_Surface *(SDLCALL *load)(SDL_RWops *src);
37 } supported[] = {
38     /* keep magicless formats first */
39     { "TGA", NULL,      IMG_LoadTGA_RW },
40     { "CUR", IMG_isCUR, IMG_LoadCUR_RW },
41     { "ICO", IMG_isICO, IMG_LoadICO_RW },
42     { "BMP", IMG_isBMP, IMG_LoadBMP_RW },
43     { "GIF", IMG_isGIF, IMG_LoadGIF_RW },
44     { "JPG", IMG_isJPG, IMG_LoadJPG_RW },
45     { "LBM", IMG_isLBM, IMG_LoadLBM_RW },
46     { "PCX", IMG_isPCX, IMG_LoadPCX_RW },
47     { "PNG", IMG_isPNG, IMG_LoadPNG_RW },
48     { "PNM", IMG_isPNM, IMG_LoadPNM_RW }, /* P[BGP]M share code */
49     { "SVG", IMG_isSVG, IMG_LoadSVG_RW },
50     { "TIF", IMG_isTIF, IMG_LoadTIF_RW },
51     { "XCF", IMG_isXCF, IMG_LoadXCF_RW },
52     { "XPM", IMG_isXPM, IMG_LoadXPM_RW },
53     { "XV",  IMG_isXV,  IMG_LoadXV_RW  },
54     { "WEBP", IMG_isWEBP, IMG_LoadWEBP_RW },
55 };
56 
IMG_Linked_Version(void)57 const SDL_version *IMG_Linked_Version(void)
58 {
59     static SDL_version linked_version;
60     SDL_IMAGE_VERSION(&linked_version);
61     return(&linked_version);
62 }
63 
64 extern int IMG_InitJPG(void);
65 extern void IMG_QuitJPG(void);
66 extern int IMG_InitPNG(void);
67 extern void IMG_QuitPNG(void);
68 extern int IMG_InitTIF(void);
69 extern void IMG_QuitTIF(void);
70 
71 extern int IMG_InitWEBP(void);
72 extern void IMG_QuitWEBP(void);
73 
74 static int initialized = 0;
75 
IMG_Init(int flags)76 int IMG_Init(int flags)
77 {
78     int result = 0;
79 
80     /* Passing 0 returns the currently initialized loaders */
81     if (!flags) {
82         return initialized;
83     }
84 
85     if (flags & IMG_INIT_JPG) {
86         if ((initialized & IMG_INIT_JPG) || IMG_InitJPG() == 0) {
87             result |= IMG_INIT_JPG;
88         }
89     }
90     if (flags & IMG_INIT_PNG) {
91         if ((initialized & IMG_INIT_PNG) || IMG_InitPNG() == 0) {
92             result |= IMG_INIT_PNG;
93         }
94     }
95     if (flags & IMG_INIT_TIF) {
96         if ((initialized & IMG_INIT_TIF) || IMG_InitTIF() == 0) {
97             result |= IMG_INIT_TIF;
98         }
99     }
100     if (flags & IMG_INIT_WEBP) {
101         if ((initialized & IMG_INIT_WEBP) || IMG_InitWEBP() == 0) {
102             result |= IMG_INIT_WEBP;
103         }
104     }
105     initialized |= result;
106 
107     return result;
108 }
109 
IMG_Quit()110 void IMG_Quit()
111 {
112     if (initialized & IMG_INIT_JPG) {
113         IMG_QuitJPG();
114     }
115     if (initialized & IMG_INIT_PNG) {
116         IMG_QuitPNG();
117     }
118     if (initialized & IMG_INIT_TIF) {
119         IMG_QuitTIF();
120     }
121     if (initialized & IMG_INIT_WEBP) {
122         IMG_QuitWEBP();
123     }
124     initialized = 0;
125 }
126 
127 #if !defined(__APPLE__) || defined(SDL_IMAGE_USE_COMMON_BACKEND)
128 /* Load an image from a file */
IMG_Load(const char * file)129 SDL_Surface *IMG_Load(const char *file)
130 {
131 #if __EMSCRIPTEN__
132     int w, h;
133     char *data;
134     SDL_Surface *surf;
135 
136     data = emscripten_get_preloaded_image_data(file, &w, &h);
137     if (data != NULL) {
138         surf = SDL_CreateRGBSurface(0, w, h, 32, 0xFF, 0xFF00, 0xFF0000, 0xFF000000);
139         if (surf != NULL) {
140             memcpy(surf->pixels, data, w * h * 4);
141         }
142         free(data);
143         return surf;
144     }
145 #endif
146 
147     SDL_RWops *src = SDL_RWFromFile(file, "rb");
148     const char *ext = SDL_strrchr(file, '.');
149     if(ext) {
150         ext++;
151     }
152     if(!src) {
153         /* The error message has been set in SDL_RWFromFile */
154         return NULL;
155     }
156     return IMG_LoadTyped_RW(src, 1, ext);
157 }
158 #endif
159 
160 /* Load an image from an SDL datasource (for compatibility) */
IMG_Load_RW(SDL_RWops * src,int freesrc)161 SDL_Surface *IMG_Load_RW(SDL_RWops *src, int freesrc)
162 {
163     return IMG_LoadTyped_RW(src, freesrc, NULL);
164 }
165 
166 /* Portable case-insensitive string compare function */
IMG_string_equals(const char * str1,const char * str2)167 static int IMG_string_equals(const char *str1, const char *str2)
168 {
169     while ( *str1 && *str2 ) {
170         if ( SDL_toupper((unsigned char)*str1) !=
171              SDL_toupper((unsigned char)*str2) )
172             break;
173         ++str1;
174         ++str2;
175     }
176     return (!*str1 && !*str2);
177 }
178 
179 /* Load an image from an SDL datasource, optionally specifying the type */
IMG_LoadTyped_RW(SDL_RWops * src,int freesrc,const char * type)180 SDL_Surface *IMG_LoadTyped_RW(SDL_RWops *src, int freesrc, const char *type)
181 {
182     int i;
183     SDL_Surface *image;
184 
185     /* Make sure there is something to do.. */
186     if ( src == NULL ) {
187         IMG_SetError("Passed a NULL data source");
188         return(NULL);
189     }
190 
191     /* See whether or not this data source can handle seeking */
192     if ( SDL_RWseek(src, 0, RW_SEEK_CUR) < 0 ) {
193         IMG_SetError("Can't seek in this data source");
194         if(freesrc)
195             SDL_RWclose(src);
196         return(NULL);
197     }
198 
199 #ifdef __EMSCRIPTEN__
200     /*load through preloadedImages*/
201 
202     if ( src->type == SDL_RWOPS_STDFILE ) {
203         int w, h, success;
204         char *data;
205         SDL_Surface *surf;
206 
207         data = emscripten_get_preloaded_image_data_from_FILE(src->hidden.stdio.fp, &w, &h);
208 
209         if(data)
210         {
211             surf = SDL_CreateRGBSurface(0, w, h, 32, 0xFF, 0xFF00, 0xFF0000, 0xFF000000);
212             if (surf != NULL) {
213                 memcpy(surf->pixels, data, w * h * 4);
214             }
215             free(data);
216 
217             if(freesrc)
218                 SDL_RWclose(src);
219 
220             /* If SDL_CreateRGBSurface returns NULL, it has set the error message for us */
221             return surf;
222         }
223     }
224 #endif
225 
226     /* Detect the type of image being loaded */
227     image = NULL;
228     for ( i=0; i < ARRAYSIZE(supported); ++i ) {
229         if(supported[i].is) {
230             if(!supported[i].is(src))
231                 continue;
232         } else {
233             /* magicless format */
234             if(!type
235                || !IMG_string_equals(type, supported[i].type))
236                 continue;
237         }
238 #ifdef DEBUG_IMGLIB
239         fprintf(stderr, "IMGLIB: Loading image as %s\n",
240             supported[i].type);
241 #endif
242         long long start = aos_now_ms();
243         image = supported[i].load(src);
244         printf("load image duration %d ms\n", (int)(aos_now_ms() - start));
245         if(freesrc)
246             SDL_RWclose(src);
247         return image;
248     }
249 
250     if ( freesrc ) {
251         SDL_RWclose(src);
252     }
253     IMG_SetError("Unsupported image format");
254     return NULL;
255 }
256 
257 #if SDL_VERSION_ATLEAST(2,0,0)
IMG_LoadTexture(SDL_Renderer * renderer,const char * file)258 SDL_Texture *IMG_LoadTexture(SDL_Renderer *renderer, const char *file)
259 {
260     SDL_Texture *texture = NULL;
261     SDL_Surface *surface = IMG_Load(file);
262     if (surface) {
263         texture = SDL_CreateTextureFromSurface(renderer, surface);
264         SDL_FreeSurface(surface);
265     }
266     return texture;
267 }
268 
IMG_LoadTexture_RW(SDL_Renderer * renderer,SDL_RWops * src,int freesrc)269 SDL_Texture *IMG_LoadTexture_RW(SDL_Renderer *renderer, SDL_RWops *src, int freesrc)
270 {
271     SDL_Texture *texture = NULL;
272     SDL_Surface *surface = IMG_Load_RW(src, freesrc);
273     if (surface) {
274         texture = SDL_CreateTextureFromSurface(renderer, surface);
275         SDL_FreeSurface(surface);
276     }
277     return texture;
278 }
279 
IMG_LoadTextureTyped_RW(SDL_Renderer * renderer,SDL_RWops * src,int freesrc,const char * type)280 SDL_Texture *IMG_LoadTextureTyped_RW(SDL_Renderer *renderer, SDL_RWops *src, int freesrc, const char *type)
281 {
282     SDL_Texture *texture = NULL;
283     SDL_Surface *surface = IMG_LoadTyped_RW(src, freesrc, type);
284     if (surface) {
285         texture = SDL_CreateTextureFromSurface(renderer, surface);
286         SDL_FreeSurface(surface);
287     }
288     return texture;
289 }
290 #endif /* SDL 2.0 */
291