projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| e7190fc7 | 1 | /* Utilities functions to read/parse Linux procfs and sysfs. |
| dff8da6b | 2 | Copyright (C) 2023-2024 Free Software Foundation, Inc. |
| e7190fc7 AZN |
3 | This file is part of the GNU C Library. |
| 4 | ||
| 5 | The GNU C Library is free software; you can redistribute it and/or | |
| 6 | modify it under the terms of the GNU Lesser General Public | |
| 7 | License as published by the Free Software Foundation; either | |
| 8 | version 2.1 of the License, or (at your option) any later version. | |
| 9 | ||
| 10 | The GNU C Library is distributed in the hope that it will be useful, | |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 | Lesser General Public License for more details. | |
| 14 | ||
| 15 | You should have received a copy of the GNU Lesser General Public | |
| 16 | License along with the GNU C Library; if not, see | |
| 17 | <https://www.gnu.org/licenses/>. */ | |
| 18 | ||
| 19 | #include <assert.h> | |
| 20 | #include <not-cancel.h> | |
| 21 | #include <procutils.h> | |
| 22 | #include <string.h> | |
| 23 | ||
| 24 | static int | |
| 25 | next_line (char **r, int fd, char *const buffer, char **cp, char **re, | |
| 26 | char *const buffer_end) | |
| 27 | { | |
| 28 | char *res = *cp; | |
| 29 | char *nl = memchr (*cp, '\n', *re - *cp); | |
| 30 | if (nl == NULL) | |
| 31 | { | |
| 32 | if (*cp != buffer) | |
| 33 | { | |
| 34 | if (*re == buffer_end) | |
| 35 | { | |
| 36 | memmove (buffer, *cp, *re - *cp); | |
| 37 | *re = buffer + (*re - *cp); | |
| 38 | *cp = buffer; | |
| 39 | ||
| 40 | ssize_t n = TEMP_FAILURE_RETRY ( | |
| 41 | __read_nocancel (fd, *re, buffer_end - *re)); | |
| 42 | if (n < 0) | |
| 43 | return -1; | |
| 44 | ||
| 45 | *re += n; | |
| 46 | ||
| 47 | nl = memchr (*cp, '\n', *re - *cp); | |
| 48 | if (nl == NULL) | |
| 49 | /* Line too long. */ | |
| 50 | return 0; | |
| 51 | } | |
| 52 | else | |
| 53 | nl = memchr (*cp, '\n', *re - *cp); | |
| 54 | ||
| 55 | res = *cp; | |
| 56 | } | |
| 57 | ||
| 58 | if (nl == NULL) | |
| 59 | nl = *re - 1; | |
| 60 | } | |
| 61 | ||
| 62 | *nl = '\0'; | |
| 63 | *cp = nl + 1; | |
| 64 | assert (*cp <= *re); | |
| 65 | ||
| 66 | if (res == *re) | |
| 67 | return 0; | |
| 68 | ||
| 69 | *r = res; | |
| 70 | return 1; | |
| 71 | } | |
| 72 | ||
| 73 | bool | |
| 74 | procutils_read_file (const char *filename, procutils_closure_t closure, | |
| 75 | void *arg) | |
| 76 | { | |
| 77 | enum { buffer_size = PROCUTILS_MAX_LINE_LEN }; | |
| 78 | char buffer[buffer_size]; | |
| 79 | char *buffer_end = buffer + buffer_size; | |
| 80 | char *cp = buffer_end; | |
| 81 | char *re = buffer_end; | |
| 82 | ||
| 83 | int fd = TEMP_FAILURE_RETRY ( | |
| 84 | __open64_nocancel (filename, O_RDONLY | O_CLOEXEC)); | |
| 85 | if (fd == -1) | |
| 86 | return false; | |
| 87 | ||
| 88 | char *l; | |
| 89 | int r; | |
| 90 | while ((r = next_line (&l, fd, buffer, &cp, &re, buffer_end)) > 0) | |
| 91 | if (closure (l, arg) != 0) | |
| 92 | break; | |
| 93 | ||
| 94 | __close_nocancel_nostatus (fd); | |
| 95 | ||
| 96 | return r == 1; | |
| 97 | } |