1 #include <stdbool.h>
2 #include <stdint.h>
3 #include <stdlib.h>
4 #include <string.h>
5 #include <alloca.h>
6 #include <errno.h>
7
8 #include <sys/types.h>
9 #include <sys/stat.h>
10 #include <unistd.h>
11 #include <fcntl.h>
12
13 #if CPUINFO_MOCK
14 #include <cpuinfo-mock.h>
15 #endif
16 #include <linux/api.h>
17 #include <cpuinfo/log.h>
18
19
cpuinfo_linux_parse_multiline_file(const char * filename,size_t buffer_size,cpuinfo_line_callback callback,void * context)20 bool cpuinfo_linux_parse_multiline_file(const char* filename, size_t buffer_size, cpuinfo_line_callback callback, void* context)
21 {
22 int file = -1;
23 bool status = false;
24 char* buffer = (char*) alloca(buffer_size);
25
26 #if CPUINFO_MOCK
27 file = cpuinfo_mock_open(filename, O_RDONLY);
28 #else
29 file = open(filename, O_RDONLY);
30 #endif
31 if (file == -1) {
32 cpuinfo_log_info("failed to open %s: %s", filename, strerror(errno));
33 goto cleanup;
34 }
35
36 /* Only used for error reporting */
37 size_t position = 0;
38 uint64_t line_number = 1;
39 const char* buffer_end = &buffer[buffer_size];
40 char* data_start = buffer;
41 ssize_t bytes_read;
42 do {
43 #if CPUINFO_MOCK
44 bytes_read = cpuinfo_mock_read(file, data_start, (size_t) (buffer_end - data_start));
45 #else
46 bytes_read = read(file, data_start, (size_t) (buffer_end - data_start));
47 #endif
48 if (bytes_read < 0) {
49 cpuinfo_log_info("failed to read file %s at position %zu: %s",
50 filename, position, strerror(errno));
51 goto cleanup;
52 }
53
54 position += (size_t) bytes_read;
55 const char* data_end = data_start + (size_t) bytes_read;
56 const char* line_start = buffer;
57
58 if (bytes_read == 0) {
59 /* No more data in the file: process the remaining text in the buffer as a single entry */
60 const char* line_end = data_end;
61 if (!callback(line_start, line_end, context, line_number)) {
62 goto cleanup;
63 }
64 } else {
65 const char* line_end;
66 do {
67 /* Find the end of the entry, as indicated by newline character ('\n') */
68 for (line_end = line_start; line_end != data_end; line_end++) {
69 if (*line_end == '\n') {
70 break;
71 }
72 }
73
74 /*
75 * If we located separator at the end of the entry, parse it.
76 * Otherwise, there may be more data at the end; read the file once again.
77 */
78 if (line_end != data_end) {
79 if (!callback(line_start, line_end, context, line_number++)) {
80 goto cleanup;
81 }
82 line_start = line_end + 1;
83 }
84 } while (line_end != data_end);
85
86 /* Move remaining partial line data at the end to the beginning of the buffer */
87 const size_t line_length = (size_t) (line_end - line_start);
88 memmove(buffer, line_start, line_length);
89 data_start = &buffer[line_length];
90 }
91 } while (bytes_read != 0);
92
93 /* Commit */
94 status = true;
95
96 cleanup:
97 if (file != -1) {
98 #if CPUINFO_MOCK
99 cpuinfo_mock_close(file);
100 #else
101 close(file);
102 #endif
103 file = -1;
104 }
105 return status;
106 }
107