1 /*
2 * Copyright 2013 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "SkOSFile.h"
9 #include "SkString.h"
10 #include "SkTFitsIn.h"
11 #include "SkTemplates.h"
12 #include "SkTypes.h"
13
14 #include <dirent.h>
15 #include <stdio.h>
16 #include <string.h>
17 #include <sys/mman.h>
18 #include <sys/stat.h>
19 #include <sys/types.h>
20 #include <unistd.h>
21
sk_exists(const char * path,SkFILE_Flags flags)22 bool sk_exists(const char *path, SkFILE_Flags flags) {
23 int mode = F_OK;
24 if (flags & kRead_SkFILE_Flag) {
25 mode |= R_OK;
26 }
27 if (flags & kWrite_SkFILE_Flag) {
28 mode |= W_OK;
29 }
30 return (0 == access(path, mode));
31 }
32
33 typedef struct {
34 dev_t dev;
35 ino_t ino;
36 } SkFILEID;
37
sk_ino(FILE * a,SkFILEID * id)38 static bool sk_ino(FILE* a, SkFILEID* id) {
39 int fd = fileno(a);
40 if (fd < 0) {
41 return 0;
42 }
43 struct stat status;
44 if (0 != fstat(fd, &status)) {
45 return 0;
46 }
47 id->dev = status.st_dev;
48 id->ino = status.st_ino;
49 return true;
50 }
51
sk_fidentical(FILE * a,FILE * b)52 bool sk_fidentical(FILE* a, FILE* b) {
53 SkFILEID aID, bID;
54 return sk_ino(a, &aID) && sk_ino(b, &bID)
55 && aID.ino == bID.ino
56 && aID.dev == bID.dev;
57 }
58
sk_fmunmap(const void * addr,size_t length)59 void sk_fmunmap(const void* addr, size_t length) {
60 munmap(const_cast<void*>(addr), length);
61 }
62
sk_fdmmap(int fd,size_t * size)63 void* sk_fdmmap(int fd, size_t* size) {
64 struct stat status;
65 if (0 != fstat(fd, &status)) {
66 return nullptr;
67 }
68 if (!S_ISREG(status.st_mode)) {
69 return nullptr;
70 }
71 if (!SkTFitsIn<size_t>(status.st_size)) {
72 return nullptr;
73 }
74 size_t fileSize = static_cast<size_t>(status.st_size);
75
76 void* addr = mmap(nullptr, fileSize, PROT_READ, MAP_PRIVATE, fd, 0);
77 if (MAP_FAILED == addr) {
78 return nullptr;
79 }
80
81 *size = fileSize;
82 return addr;
83 }
84
sk_fileno(FILE * f)85 int sk_fileno(FILE* f) {
86 return fileno(f);
87 }
88
sk_fmmap(FILE * f,size_t * size)89 void* sk_fmmap(FILE* f, size_t* size) {
90 int fd = sk_fileno(f);
91 if (fd < 0) {
92 return nullptr;
93 }
94
95 return sk_fdmmap(fd, size);
96 }
97
sk_qread(FILE * file,void * buffer,size_t count,size_t offset)98 size_t sk_qread(FILE* file, void* buffer, size_t count, size_t offset) {
99 int fd = sk_fileno(file);
100 if (fd < 0) {
101 return SIZE_MAX;
102 }
103 ssize_t bytesRead = pread(fd, buffer, count, offset);
104 if (bytesRead < 0) {
105 return SIZE_MAX;
106 }
107 return bytesRead;
108 }
109
110 ////////////////////////////////////////////////////////////////////////////
111
112 struct SkOSFileIterData {
SkOSFileIterDataSkOSFileIterData113 SkOSFileIterData() : fDIR(0) { }
114 DIR* fDIR;
115 SkString fPath, fSuffix;
116 };
117 static_assert(sizeof(SkOSFileIterData) <= SkOSFile::Iter::kStorageSize, "not_enough_space");
118
Iter()119 SkOSFile::Iter::Iter() { new (fSelf.get()) SkOSFileIterData; }
120
Iter(const char path[],const char suffix[])121 SkOSFile::Iter::Iter(const char path[], const char suffix[]) {
122 new (fSelf.get()) SkOSFileIterData;
123 this->reset(path, suffix);
124 }
125
~Iter()126 SkOSFile::Iter::~Iter() {
127 SkOSFileIterData& self = *static_cast<SkOSFileIterData*>(fSelf.get());
128 if (self.fDIR) {
129 ::closedir(self.fDIR);
130 }
131 self.~SkOSFileIterData();
132 }
133
reset(const char path[],const char suffix[])134 void SkOSFile::Iter::reset(const char path[], const char suffix[]) {
135 SkOSFileIterData& self = *static_cast<SkOSFileIterData*>(fSelf.get());
136 if (self.fDIR) {
137 ::closedir(self.fDIR);
138 self.fDIR = 0;
139 }
140
141 self.fPath.set(path);
142 if (path) {
143 self.fDIR = ::opendir(path);
144 self.fSuffix.set(suffix);
145 } else {
146 self.fSuffix.reset();
147 }
148 }
149
150 // returns true if suffix is empty, or if str ends with suffix
issuffixfor(const SkString & suffix,const char str[])151 static bool issuffixfor(const SkString& suffix, const char str[]) {
152 size_t suffixLen = suffix.size();
153 size_t strLen = strlen(str);
154
155 return strLen >= suffixLen &&
156 memcmp(suffix.c_str(), str + strLen - suffixLen, suffixLen) == 0;
157 }
158
next(SkString * name,bool getDir)159 bool SkOSFile::Iter::next(SkString* name, bool getDir) {
160 SkOSFileIterData& self = *static_cast<SkOSFileIterData*>(fSelf.get());
161 if (self.fDIR) {
162 dirent* entry;
163
164 while ((entry = ::readdir(self.fDIR)) != nullptr) {
165 struct stat s;
166 SkString str(self.fPath);
167
168 if (!str.endsWith("/") && !str.endsWith("\\")) {
169 str.append("/");
170 }
171 str.append(entry->d_name);
172
173 if (0 == stat(str.c_str(), &s)) {
174 if (getDir) {
175 if (s.st_mode & S_IFDIR) {
176 break;
177 }
178 } else {
179 if (!(s.st_mode & S_IFDIR) && issuffixfor(self.fSuffix, entry->d_name)) {
180 break;
181 }
182 }
183 }
184 }
185 if (entry) { // we broke out with a file
186 if (name) {
187 name->set(entry->d_name);
188 }
189 return true;
190 }
191 }
192 return false;
193 }
194