| 1 | #ifndef _BABELTRACE_COMPAT_STDIO_H |
| 2 | #define _BABELTRACE_COMPAT_STDIO_H |
| 3 | |
| 4 | /* |
| 5 | * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 6 | * |
| 7 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 8 | * of this software and associated documentation files (the "Software"), to deal |
| 9 | * in the Software without restriction, including without limitation the rights |
| 10 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 11 | * copies of the Software, and to permit persons to whom the Software is |
| 12 | * furnished to do so, subject to the following conditions: |
| 13 | * |
| 14 | * The above copyright notice and this permission notice shall be included in |
| 15 | * all copies or substantial portions of the Software. |
| 16 | * |
| 17 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 18 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 19 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 20 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 21 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 22 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| 23 | * SOFTWARE. |
| 24 | */ |
| 25 | |
| 26 | #include <stdio.h> |
| 27 | #include <errno.h> |
| 28 | #include <assert.h> |
| 29 | |
| 30 | #define BT_GETLINE_MINBUFLEN 64 |
| 31 | |
| 32 | static inline |
| 33 | char * _bt_getline_bufalloc(char **lineptr, size_t *n, size_t linelen) |
| 34 | { |
| 35 | size_t buflen = *n; |
| 36 | char *buf = *lineptr; |
| 37 | |
| 38 | if (buflen >= linelen && buf != NULL) { |
| 39 | return buf; |
| 40 | } |
| 41 | if (buf == NULL) { |
| 42 | buflen = BT_GETLINE_MINBUFLEN; |
| 43 | } else { |
| 44 | buflen = buflen << 1; |
| 45 | if (buflen < BT_GETLINE_MINBUFLEN) { |
| 46 | buflen = BT_GETLINE_MINBUFLEN; |
| 47 | } |
| 48 | } |
| 49 | /* Check below not strictly needed, extra safety. */ |
| 50 | if (buflen < linelen) { |
| 51 | buflen = linelen; |
| 52 | } |
| 53 | buf = realloc(buf, buflen); |
| 54 | if (!buf) { |
| 55 | errno = ENOMEM; |
| 56 | return NULL; |
| 57 | } |
| 58 | *n = buflen; |
| 59 | *lineptr = buf; |
| 60 | return buf; |
| 61 | } |
| 62 | |
| 63 | /* |
| 64 | * Returns line length (including possible final \n, excluding final |
| 65 | * \0). On end of file, returns -1 with nonzero feof(stream) and errno |
| 66 | * set to 0. On error, returns -1 with errno set. |
| 67 | * |
| 68 | * This interface is similar to the getline(3) man page part of the |
| 69 | * Linux man-pages project, release 3.74. One major difference from the |
| 70 | * Open Group POSIX specification is that this implementation does not |
| 71 | * necessarily set the ferror() flag on error (because it is internal to |
| 72 | * libc). |
| 73 | */ |
| 74 | static inline |
| 75 | ssize_t bt_getline(char **lineptr, size_t *n, FILE *stream) |
| 76 | { |
| 77 | size_t linelen = 0; |
| 78 | char *buf; |
| 79 | int found_eof = 0; |
| 80 | |
| 81 | if (lineptr == NULL || n == NULL) { |
| 82 | errno = EINVAL; |
| 83 | return -1; |
| 84 | } |
| 85 | for (;;) { |
| 86 | char c; |
| 87 | |
| 88 | c = fgetc(stream); |
| 89 | if (c == EOF) { |
| 90 | if (ferror(stream)) { |
| 91 | /* ferror() is set, errno set by fgetc(). */ |
| 92 | return -1; |
| 93 | } |
| 94 | assert(feof(stream)); |
| 95 | found_eof = 1; |
| 96 | break; |
| 97 | } |
| 98 | if (linelen == SSIZE_MAX) { |
| 99 | errno = EOVERFLOW; |
| 100 | return -1; |
| 101 | } |
| 102 | buf = _bt_getline_bufalloc(lineptr, n, ++linelen); |
| 103 | if (!buf) { |
| 104 | return -1; |
| 105 | } |
| 106 | buf[linelen - 1] = c; |
| 107 | if (c == '\n') { |
| 108 | break; |
| 109 | } |
| 110 | } |
| 111 | if (!linelen && found_eof) { |
| 112 | /* feof() is set. */ |
| 113 | errno = 0; |
| 114 | return -1; |
| 115 | } |
| 116 | buf = _bt_getline_bufalloc(lineptr, n, ++linelen); |
| 117 | if (!buf) { |
| 118 | return -1; |
| 119 | } |
| 120 | buf[linelen - 1] = '\0'; |
| 121 | return linelen - 1; /* Count don't include final \0. */ |
| 122 | } |
| 123 | |
| 124 | #endif /* _BABELTRACE_COMPAT_STDIO_H */ |