src/lib/image.c
changeset 17 baf3fe7c6354
parent 11 eb2a1472f084
child 18 f92a24ab046e
equal deleted inserted replaced
16:6e781cf3d459 17:baf3fe7c6354
     1 #include "image.h"
     1 #include "image.h"
     2 #include "cache.h"
     2 #include "cache.h"
       
     3 #include "error.h"
     3 #include "shared/util.h"
     4 #include "shared/util.h"
     4 
     5 
     5 #include <stdlib.h>
     6 #include <stdlib.h>
     6 #include <errno.h>
     7 #include <errno.h>
     7 
     8 
     8 #include <png.h>
     9 #include <png.h>
     9 
    10 
    10 static int pt_image_new (struct pt_image **img_ptr, struct pt_ctx *ctx, const char *path)
    11 static int pt_image_new (struct pt_image **image_ptr, struct pt_ctx *ctx, const char *path)
    11 {
    12 {
    12     struct pt_image *img;
    13     struct pt_image *image;
       
    14     int err = 0;
    13 
    15 
    14     // alloc
    16     // alloc
    15     if ((img = calloc(1, sizeof(*img))) == NULL)
    17     if ((image = calloc(1, sizeof(*image))) == NULL)
    16         return -1;
    18         JUMP_SET_ERROR(err, PT_ERR_MEM);
    17 
    19 
    18     if ((img->path = strdup(path)) == NULL)
    20     if ((image->path = strdup(path)) == NULL)
    19         goto error;
    21         JUMP_SET_ERROR(err, PT_ERR_MEM);
    20 
    22 
    21     // init
    23     // init
    22     img->ctx = ctx;
    24     image->ctx = ctx;
    23     
    25     
    24     // ok
    26     // ok
    25     *img_ptr = img;
    27     *image_ptr = image;
    26 
    28 
    27     return 0;
    29     return 0;
    28 
    30 
    29 error:
    31 error:
    30     pt_image_destroy(img);
    32     pt_image_destroy(image);
    31 
    33     
    32     return -1;
    34     return err;
    33 }
    35 }
    34 
    36 
    35 /**
    37 /**
    36  * Open the image's FILE
    38  * Open the image's FILE
    37  */
    39  */
    38 static int pt_image_open_file (struct pt_image *img, FILE **file_ptr)
    40 static int pt_image_open_file (struct pt_image *image, FILE **file_ptr)
    39 {
    41 {
    40     FILE *fp;
    42     FILE *fp;
    41     
    43     
    42     // open
    44     // open
    43     if ((fp = fopen(img->path, "rb")) < 0)
    45     if ((fp = fopen(image->path, "rb")) == NULL)
    44         return -1;
    46         RETURN_ERROR(PT_ERR_IMG_FOPEN);
    45 
    47 
    46     // ok
    48     // ok
    47     *file_ptr = fp;
    49     *file_ptr = fp;
    48 
    50 
    49     return 0;
    51     return 0;
    50 }
    52 }
    51 
    53 
    52 /**
    54 /**
    53  * Open the PNG image, setting up the I/O and returning the png_structp and png_infop
    55  * Open the PNG image, setting up the I/O and returning the png_structp and png_infop
    54  */
    56  */
    55 static int pt_image_open_png (struct pt_image *img, png_structp *png_ptr, png_infop *info_ptr)
    57 static int pt_image_open_png (struct pt_image *image, png_structp *png_ptr, png_infop *info_ptr)
    56 {
    58 {
    57     FILE *fp = NULL;
    59     FILE *fp = NULL;
    58     png_structp png = NULL;
    60     png_structp png = NULL;
    59     png_infop info = NULL;
    61     png_infop info = NULL;
       
    62     int err;
    60     
    63     
    61     // open I/O
    64     // open I/O
    62     if (pt_image_open_file(img, &fp))
    65     if ((err = pt_image_open_file(image, &fp)))
    63         goto error;
    66         JUMP_ERROR(err);
    64 
    67 
    65     // create the struct
    68     // create the struct
    66     if ((png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL)) == NULL)
    69     if ((png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL)) == NULL)
    67         goto error;
    70         JUMP_SET_ERROR(err, PT_ERR_PNG_CREATE);
    68 
    71 
    69     // create the info
    72     // create the info
    70     if ((info = png_create_info_struct(png)) == NULL)
    73     if ((info = png_create_info_struct(png)) == NULL)
    71         goto error;
    74         JUMP_SET_ERROR(err, PT_ERR_PNG_CREATE);
    72 
    75 
    73     // setup error trap for the I/O
    76     // setup error trap for the I/O
    74     if (setjmp(png_jmpbuf(png)))
    77     if (setjmp(png_jmpbuf(png)))
    75         goto error;
    78         JUMP_SET_ERROR(err, PT_ERR_PNG);
    76     
    79     
    77     // setup I/O to FILE
    80     // setup I/O to FILE
    78     png_init_io(png, fp);
    81     png_init_io(png, fp);
    79 
    82 
    80     // ok
    83     // ok
    81     // XXX: what to do with fp?
    84     // XXX: what to do with fp? Should fclose() when done?
    82     *png_ptr = png;
    85     *png_ptr = png;
    83     *info_ptr = info;
    86     *info_ptr = info;
    84 
    87 
    85     return 0;
    88     return 0;
    86 
    89 
    88     // cleanup file
    91     // cleanup file
    89     if (fp) fclose(fp);
    92     if (fp) fclose(fp);
    90 
    93 
    91     // cleanup PNG state
    94     // cleanup PNG state
    92     png_destroy_read_struct(&png, &info, NULL);
    95     png_destroy_read_struct(&png, &info, NULL);
    93 
    96     
    94     return -1;
    97     return err;
    95 }
    98 }
    96 
    99 
    97 /**
   100 /**
    98  * Update the image_info field from the given png object.
   101  * Update the image_info field from the given png object.
    99  *
   102  *
   113  */
   116  */
   114 static int pt_image_update_cache (struct pt_image *image)
   117 static int pt_image_update_cache (struct pt_image *image)
   115 {
   118 {
   116     png_structp png;
   119     png_structp png;
   117     png_infop info;
   120     png_infop info;
       
   121     int err = 0;
   118 
   122 
   119     // pre-check enabled
   123     // pre-check enabled
   120     if (!(image->cache->mode & PT_OPEN_UPDATE)) {
   124     if (!(image->cache->mode & PT_OPEN_UPDATE))
   121         errno = EPERM;
   125         RETURN_ERROR_ERRNO(PT_ERR_OPEN_MODE, EACCES);
   122         return -1;
       
   123     }
       
   124 
   126 
   125     // open .png
   127     // open .png
   126     if (pt_image_open_png(image, &png, &info))
   128     if ((err = pt_image_open_png(image, &png, &info)))
   127         return -1;
   129         return err;
   128     
   130     
   129     // setup error trap
   131     // setup error trap
   130     if (setjmp(png_jmpbuf(png)))
   132     if (setjmp(png_jmpbuf(png)))
   131         goto error;
   133         JUMP_SET_ERROR(err, PT_ERR_PNG);
   132 
   134 
   133     // read meta-info
   135     // read meta-info
   134     png_read_info(png, info);
   136     png_read_info(png, info);
   135 
   137 
   136     // update our meta-info
   138     // update our meta-info
   137     if (pt_image_update_info(image, png, info))
   139     if ((err = pt_image_update_info(image, png, info)))
   138         goto error;
   140         JUMP_ERROR(err);
   139 
   141 
   140     // pass to cache object
   142     // pass to cache object
   141     if (pt_cache_update_png(image->cache, png, info))
   143     if ((err = pt_cache_update_png(image->cache, png, info)))
   142         goto error;
   144         JUMP_ERROR(err);
   143 
   145 
   144     // finish off, ignore trailing data
   146     // finish off, ignore trailing data
   145     png_read_end(png, NULL);
   147     png_read_end(png, NULL);
   146 
   148 
       
   149 error:
   147     // clean up
   150     // clean up
       
   151     // XXX: we need to close the fopen'd .png
   148     png_destroy_read_struct(&png, &info, NULL);
   152     png_destroy_read_struct(&png, &info, NULL);
   149 
   153 
   150     return 0;
   154     return err;
   151 
       
   152 error:
       
   153     // clean up
       
   154     png_destroy_read_struct(&png, &info, NULL);
       
   155 
       
   156     return -1;
       
   157 }
   155 }
   158 
   156 
   159 /**
   157 /**
   160  * Build a filesystem path representing the appropriate path for this image's cache entry, and store it in the given
   158  * Build a filesystem path representing the appropriate path for this image's cache entry, and store it in the given
   161  * buffer.
   159  * buffer.
   162  */
   160  */
   163 static int pt_image_cache_path (struct pt_image *image, char *buf, size_t len)
   161 static int pt_image_cache_path (struct pt_image *image, char *buf, size_t len)
   164 {
   162 {
   165     return path_with_fext(image->path, buf, len, ".cache"); 
   163     if (path_with_fext(image->path, buf, len, ".cache"))
       
   164         RETURN_ERROR(PT_ERR_PATH);
       
   165 
       
   166     return 0;
   166 }
   167 }
   167 
   168 
   168 int pt_image_open (struct pt_image **image_ptr, struct pt_ctx *ctx, const char *path, int cache_mode)
   169 int pt_image_open (struct pt_image **image_ptr, struct pt_ctx *ctx, const char *path, int cache_mode)
   169 {
   170 {
   170     struct pt_image *image;
   171     struct pt_image *image;
   171     char cache_path[1024];
   172     char cache_path[1024];
       
   173     int err;
   172 
   174 
   173     // XXX: verify that the path exists and looks like a PNG file
   175     // XXX: verify that the path exists and looks like a PNG file
   174 
   176 
   175     // alloc
   177     // alloc
   176     if (pt_image_new(&image, ctx, path))
   178     if ((err = pt_image_new(&image, ctx, path)))
   177         return -1;
   179         return err;
   178     
   180     
   179     // compute cache file path
   181     // compute cache file path
   180     if (pt_image_cache_path(image, cache_path, sizeof(cache_path)))
   182     if ((err = pt_image_cache_path(image, cache_path, sizeof(cache_path))))
   181         goto error;
   183         JUMP_ERROR(err);
   182 
   184 
   183     // create the cache object for this image (doesn't yet open it)
   185     // create the cache object for this image (doesn't yet open it)
   184     if (pt_cache_new(&image->cache, cache_path, cache_mode))
   186     if ((err = pt_cache_new(&image->cache, cache_path, cache_mode)))
   185         goto error;
   187         JUMP_ERROR(err);
   186     
   188     
   187     // ok, ready for access
   189     // ok, ready for access
   188     *image_ptr = image;
   190     *image_ptr = image;
   189 
   191 
   190     return 0;
   192     return 0;
   191 
   193 
   192 error:
   194 error:
   193     pt_image_destroy(image);
   195     pt_image_destroy(image);
   194 
   196 
   195     return -1;
   197     return err;
   196 }
   198 }
   197 
   199 
   198 int pt_image_info (struct pt_image *image, const struct pt_image_info **info_ptr)
   200 int pt_image_info (struct pt_image *image, const struct pt_image_info **info_ptr)
   199 {
   201 {
       
   202     int err;
       
   203 
   200     // update info
   204     // update info
   201     if (pt_cache_info(image->cache, &image->info))
   205     if ((err = pt_cache_info(image->cache, &image->info)))
   202         return -1;
   206         return err;
   203     
   207     
   204     // return pointer
   208     // return pointer
   205     *info_ptr = &image->info;
   209     *info_ptr = &image->info;
   206 
   210 
   207     return 0;
   211     return 0;
   219 
   223 
   220 int pt_image_tile (struct pt_image *image, const struct pt_tile_info *tile_info, FILE *out)
   224 int pt_image_tile (struct pt_image *image, const struct pt_tile_info *tile_info, FILE *out)
   221 {
   225 {
   222     png_structp png = NULL;
   226     png_structp png = NULL;
   223     png_infop info = NULL;
   227     png_infop info = NULL;
       
   228     int err = 0;
   224         
   229         
   225     // open PNG writer
   230     // open PNG writer
   226     if ((png = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL)) == NULL)
   231     if ((png = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL)) == NULL)
   227         goto error;
   232         JUMP_SET_ERROR(err, PT_ERR_PNG_CREATE);
   228     
   233     
   229     if ((info = png_create_info_struct(png)) == NULL)
   234     if ((info = png_create_info_struct(png)) == NULL)
   230         goto error;
   235         JUMP_SET_ERROR(err, PT_ERR_PNG_CREATE);
   231 
   236 
   232     // libpng error trap
   237     // libpng error trap
   233     if (setjmp(png_jmpbuf(png)))
   238     if (setjmp(png_jmpbuf(png)))
   234         goto error;
   239         JUMP_SET_ERROR(err, PT_ERR_PNG);
   235     
   240     
   236     // setup IO
   241     // setup IO
   237     png_init_io(png, out);
   242     png_init_io(png, out);
   238     
   243     
   239     // render tile
   244     // render tile
   240     if (pt_cache_tile_png(image->cache, png, info, tile_info))
   245     if ((err = pt_cache_tile_png(image->cache, png, info, tile_info)))
   241         goto error;
   246         JUMP_ERROR(err);
   242 
   247 
   243     // done
   248     // done
   244     png_write_end(png, info);
   249     png_write_end(png, info);
   245 
   250 
       
   251 error:
   246     // cleanup
   252     // cleanup
   247     png_destroy_write_struct(&png, &info);
   253     png_destroy_write_struct(&png, &info);
   248 
   254 
   249     return 0;
   255     return err;
   250 
       
   251 error:
       
   252     // cleanup
       
   253     png_destroy_write_struct(&png, &info);
       
   254 
       
   255     return -1;
       
   256 }
   256 }
   257 
   257 
   258 void pt_image_destroy (struct pt_image *image)
   258 void pt_image_destroy (struct pt_image *image)
   259 {
   259 {
   260     free(image->path);
   260     free(image->path);