1// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
2// for details. All rights reserved. Use of this source code is governed by a
3// BSD-style license that can be found in the LICENSE file.
4
5#include "vm/globals.h"
6#if defined(HOST_OS_LINUX) || defined(HOST_OS_ANDROID)
7
8#include "vm/proccpuinfo.h"
9
10#include <ctype.h> // NOLINT
11#include <string.h> // NOLINT
12
13#include "platform/assert.h"
14
15namespace dart {
16
17char* ProcCpuInfo::data_ = NULL;
18intptr_t ProcCpuInfo::datalen_ = 0;
19
20void ProcCpuInfo::Init() {
21 // Get the size of the cpuinfo file by reading it until the end. This is
22 // required because files under /proc do not always return a valid size
23 // when using fseek(0, SEEK_END) + ftell(). Nor can they be mmap()-ed.
24 static const char PATHNAME[] = "/proc/cpuinfo";
25 FILE* fp = fopen(PATHNAME, "r");
26 if (fp != NULL) {
27 for (;;) {
28 char buffer[256];
29 size_t n = fread(buffer, 1, sizeof(buffer), fp);
30 if (n == 0) {
31 break;
32 }
33 datalen_ += n;
34 }
35 fclose(fp);
36 }
37
38 // Read the contents of the cpuinfo file.
39 data_ = reinterpret_cast<char*>(malloc(datalen_ + 1));
40 fp = fopen(PATHNAME, "r");
41 if (fp != NULL) {
42 for (intptr_t offset = 0; offset < datalen_;) {
43 size_t n = fread(data_ + offset, 1, datalen_ - offset, fp);
44 if (n == 0) {
45 break;
46 }
47 offset += n;
48 }
49 fclose(fp);
50 }
51
52 // Zero-terminate the data.
53 data_[datalen_] = '\0';
54}
55
56void ProcCpuInfo::Cleanup() {
57 ASSERT(data_);
58 free(data_);
59 data_ = NULL;
60}
61
62char* ProcCpuInfo::FieldStart(const char* field) {
63 // Look for first field occurrence, and ensure it starts the line.
64 size_t fieldlen = strlen(field);
65 char* p = data_;
66 for (;;) {
67 p = strstr(p, field);
68 if (p == NULL) {
69 return NULL;
70 }
71 if (p == data_ || p[-1] == '\n') {
72 break;
73 }
74 p += fieldlen;
75 }
76
77 // Skip to the first colon followed by a space.
78 p = strchr(p + fieldlen, ':');
79 if (p == NULL || (isspace(p[1]) == 0)) {
80 return NULL;
81 }
82 p += 2;
83
84 return p;
85}
86
87bool ProcCpuInfo::FieldContains(const char* field, const char* search_string) {
88 ASSERT(data_ != NULL);
89 ASSERT(search_string != NULL);
90
91 char* p = FieldStart(field);
92 if (p == NULL) {
93 return false;
94 }
95
96 // Find the end of the line.
97 char* q = strchr(p, '\n');
98 if (q == NULL) {
99 q = data_ + datalen_;
100 }
101
102 char saved_end = *q;
103 *q = '\0';
104 bool ret = (strcasestr(p, search_string) != NULL);
105 *q = saved_end;
106
107 return ret;
108}
109
110// Extract the content of a the first occurrence of a given field in
111// the content of the cpuinfo file and return it as a heap-allocated
112// string that must be freed by the caller using free.
113// Return NULL if not found.
114const char* ProcCpuInfo::ExtractField(const char* field) {
115 ASSERT(field != NULL);
116 ASSERT(data_ != NULL);
117
118 char* p = FieldStart(field);
119 if (p == NULL) {
120 return NULL;
121 }
122
123 // Find the end of the line.
124 char* q = strchr(p, '\n');
125 if (q == NULL) {
126 q = data_ + datalen_;
127 }
128
129 intptr_t len = q - p;
130 char* result = reinterpret_cast<char*>(malloc(len + 1));
131 // Copy the line into result, leaving enough room for a null-terminator.
132 char saved_end = *q;
133 *q = '\0';
134 strncpy(result, p, len);
135 result[len] = '\0';
136 *q = saved_end;
137
138 return result;
139}
140
141bool ProcCpuInfo::HasField(const char* field) {
142 ASSERT(field != NULL);
143 ASSERT(data_ != NULL);
144 return (FieldStart(field) != NULL);
145}
146
147} // namespace dart
148
149#endif // defined(HOST_OS_LINUX) || defined(HOST_OS_ANDROID)
150