1 // Copyright 2016 Google Inc. All Rights Reserved.
2 //
3 // Use of this source code is governed by a BSD-style license
4 // that can be found in the COPYING file in the root of the source
5 // tree. An additional intellectual property rights grant can be found
6 // in the file PATENTS. All contributing project authors may
7 // be found in the AUTHORS file in the root of the source tree.
8 // -----------------------------------------------------------------------------
9 //
10 // Utility functions used by the image decoders.
11 //
12
13 #include "./imageio_util.h"
14
15 #if defined(_WIN32)
16 #include <fcntl.h> // for _O_BINARY
17 #include <io.h> // for _setmode()
18 #endif
19 #include <stdlib.h>
20 #include <string.h>
21 #include "../examples/unicode.h"
22
23 // -----------------------------------------------------------------------------
24 // File I/O
25
ImgIoUtilSetBinaryMode(FILE * file)26 FILE* ImgIoUtilSetBinaryMode(FILE* file) {
27 #if defined(_WIN32)
28 if (_setmode(_fileno(file), _O_BINARY) == -1) {
29 fprintf(stderr, "Failed to reopen file in O_BINARY mode.\n");
30 return NULL;
31 }
32 #endif
33 return file;
34 }
35
ImgIoUtilReadFromStdin(const uint8_t ** data,size_t * data_size)36 int ImgIoUtilReadFromStdin(const uint8_t** data, size_t* data_size) {
37 static const size_t kBlockSize = 16384; // default initial size
38 size_t max_size = 0;
39 size_t size = 0;
40 uint8_t* input = NULL;
41
42 if (data == NULL || data_size == NULL) return 0;
43 *data = NULL;
44 *data_size = 0;
45
46 if (!ImgIoUtilSetBinaryMode(stdin)) return 0;
47
48 while (!feof(stdin)) {
49 // We double the buffer size each time and read as much as possible.
50 const size_t extra_size = (max_size == 0) ? kBlockSize : max_size;
51 // we allocate one extra byte for the \0 terminator
52 void* const new_data = realloc(input, max_size + extra_size + 1);
53 if (new_data == NULL) goto Error;
54 input = (uint8_t*)new_data;
55 max_size += extra_size;
56 size += fread(input + size, 1, extra_size, stdin);
57 if (size < max_size) break;
58 }
59 if (ferror(stdin)) goto Error;
60 if (input != NULL) input[size] = '\0'; // convenient 0-terminator
61 *data = input;
62 *data_size = size;
63 return 1;
64
65 Error:
66 free(input);
67 fprintf(stderr, "Could not read from stdin\n");
68 return 0;
69 }
70
ImgIoUtilReadFile(const char * const file_name,const uint8_t ** data,size_t * data_size)71 int ImgIoUtilReadFile(const char* const file_name,
72 const uint8_t** data, size_t* data_size) {
73 int ok;
74 uint8_t* file_data;
75 size_t file_size;
76 FILE* in;
77 const int from_stdin = (file_name == NULL) || !WSTRCMP(file_name, "-");
78
79 if (from_stdin) return ImgIoUtilReadFromStdin(data, data_size);
80
81 if (data == NULL || data_size == NULL) return 0;
82 *data = NULL;
83 *data_size = 0;
84
85 in = WFOPEN(file_name, "rb");
86 if (in == NULL) {
87 WFPRINTF(stderr, "cannot open input file '%s'\n", (const W_CHAR*)file_name);
88 return 0;
89 }
90 fseek(in, 0, SEEK_END);
91 file_size = ftell(in);
92 fseek(in, 0, SEEK_SET);
93 // we allocate one extra byte for the \0 terminator
94 file_data = (uint8_t*)WebPMalloc(file_size + 1);
95 if (file_data == NULL) {
96 fclose(in);
97 WFPRINTF(stderr, "memory allocation failure when reading file %s\n",
98 (const W_CHAR*)file_name);
99 return 0;
100 }
101 ok = (fread(file_data, file_size, 1, in) == 1);
102 fclose(in);
103
104 if (!ok) {
105 WFPRINTF(stderr, "Could not read %d bytes of data from file %s\n",
106 (int)file_size, (const W_CHAR*)file_name);
107 WebPFree(file_data);
108 return 0;
109 }
110 file_data[file_size] = '\0'; // convenient 0-terminator
111 *data = file_data;
112 *data_size = file_size;
113 return 1;
114 }
115
116 // -----------------------------------------------------------------------------
117
ImgIoUtilWriteFile(const char * const file_name,const uint8_t * data,size_t data_size)118 int ImgIoUtilWriteFile(const char* const file_name,
119 const uint8_t* data, size_t data_size) {
120 int ok;
121 FILE* out;
122 const int to_stdout = (file_name == NULL) || !WSTRCMP(file_name, "-");
123
124 if (data == NULL) {
125 return 0;
126 }
127 out = to_stdout ? ImgIoUtilSetBinaryMode(stdout) : WFOPEN(file_name, "wb");
128 if (out == NULL) {
129 WFPRINTF(stderr, "Error! Cannot open output file '%s'\n",
130 (const W_CHAR*)file_name);
131 return 0;
132 }
133 ok = (fwrite(data, data_size, 1, out) == 1);
134 if (out != stdout) fclose(out);
135 return ok;
136 }
137
138 // -----------------------------------------------------------------------------
139
ImgIoUtilCopyPlane(const uint8_t * src,int src_stride,uint8_t * dst,int dst_stride,int width,int height)140 void ImgIoUtilCopyPlane(const uint8_t* src, int src_stride,
141 uint8_t* dst, int dst_stride, int width, int height) {
142 while (height-- > 0) {
143 memcpy(dst, src, width * sizeof(*dst));
144 src += src_stride;
145 dst += dst_stride;
146 }
147 }
148
149 // -----------------------------------------------------------------------------
150
ImgIoUtilCheckSizeArgumentsOverflow(uint64_t stride,size_t height)151 int ImgIoUtilCheckSizeArgumentsOverflow(uint64_t stride, size_t height) {
152 const uint64_t total_size = stride * height;
153 int ok = (total_size == (size_t)total_size);
154 // check that 'stride' is representable as int:
155 ok = ok && ((uint64_t)(int)stride == stride);
156 #if defined(WEBP_MAX_IMAGE_SIZE)
157 ok = ok && (total_size <= (uint64_t)WEBP_MAX_IMAGE_SIZE);
158 #endif
159 return ok;
160 }
161
162 // -----------------------------------------------------------------------------
163