Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 2 | #include "debug.h" |
Arnaldo Carvalho de Melo | e7f01d1 | 2012-03-14 12:29:29 -0300 | [diff] [blame] | 3 | #include <linux/kernel.h> |
Arnaldo Carvalho de Melo | 7f7c536 | 2019-07-04 11:32:27 -0300 | [diff] [blame] | 4 | #include <linux/zalloc.h> |
Arnaldo Carvalho de Melo | a43783a | 2017-04-18 10:46:11 -0300 | [diff] [blame] | 5 | #include <errno.h> |
Arnaldo Carvalho de Melo | 215a0d3 | 2019-07-04 11:21:24 -0300 | [diff] [blame] | 6 | #include <stdlib.h> |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 7 | |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 8 | /* |
| 9 | * Used as the default ->buf value, so that people can always assume |
| 10 | * buf is non NULL and ->buf is NUL terminated even for a freshly |
| 11 | * initialized strbuf. |
| 12 | */ |
| 13 | char strbuf_slopbuf[1]; |
| 14 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 15 | int strbuf_init(struct strbuf *sb, ssize_t hint) |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 16 | { |
| 17 | sb->alloc = sb->len = 0; |
| 18 | sb->buf = strbuf_slopbuf; |
| 19 | if (hint) |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 20 | return strbuf_grow(sb, hint); |
| 21 | return 0; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 22 | } |
| 23 | |
| 24 | void strbuf_release(struct strbuf *sb) |
| 25 | { |
| 26 | if (sb->alloc) { |
Arnaldo Carvalho de Melo | 74cf249 | 2013-12-27 16:55:14 -0300 | [diff] [blame] | 27 | zfree(&sb->buf); |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 28 | strbuf_init(sb, 0); |
| 29 | } |
| 30 | } |
| 31 | |
| 32 | char *strbuf_detach(struct strbuf *sb, size_t *sz) |
| 33 | { |
| 34 | char *res = sb->alloc ? sb->buf : NULL; |
| 35 | if (sz) |
| 36 | *sz = sb->len; |
| 37 | strbuf_init(sb, 0); |
| 38 | return res; |
| 39 | } |
| 40 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 41 | int strbuf_grow(struct strbuf *sb, size_t extra) |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 42 | { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 43 | char *buf; |
| 44 | size_t nr = sb->len + extra + 1; |
| 45 | |
| 46 | if (nr < sb->alloc) |
| 47 | return 0; |
| 48 | |
| 49 | if (nr <= sb->len) |
| 50 | return -E2BIG; |
| 51 | |
| 52 | if (alloc_nr(sb->alloc) > nr) |
| 53 | nr = alloc_nr(sb->alloc); |
| 54 | |
| 55 | /* |
| 56 | * Note that sb->buf == strbuf_slopbuf if sb->alloc == 0, and it is |
| 57 | * a static variable. Thus we have to avoid passing it to realloc. |
| 58 | */ |
| 59 | buf = realloc(sb->alloc ? sb->buf : NULL, nr * sizeof(*buf)); |
| 60 | if (!buf) |
| 61 | return -ENOMEM; |
| 62 | |
| 63 | sb->buf = buf; |
| 64 | sb->alloc = nr; |
| 65 | return 0; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 66 | } |
| 67 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 68 | int strbuf_addch(struct strbuf *sb, int c) |
Arnaldo Carvalho de Melo | 0741208 | 2016-03-23 16:56:56 -0300 | [diff] [blame] | 69 | { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 70 | int ret = strbuf_grow(sb, 1); |
| 71 | if (ret) |
| 72 | return ret; |
| 73 | |
Arnaldo Carvalho de Melo | 0741208 | 2016-03-23 16:56:56 -0300 | [diff] [blame] | 74 | sb->buf[sb->len++] = c; |
| 75 | sb->buf[sb->len] = '\0'; |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 76 | return 0; |
Arnaldo Carvalho de Melo | 0741208 | 2016-03-23 16:56:56 -0300 | [diff] [blame] | 77 | } |
| 78 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 79 | int strbuf_add(struct strbuf *sb, const void *data, size_t len) |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 80 | { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 81 | int ret = strbuf_grow(sb, len); |
| 82 | if (ret) |
| 83 | return ret; |
| 84 | |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 85 | memcpy(sb->buf + sb->len, data, len); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 86 | return strbuf_setlen(sb, sb->len + len); |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 87 | } |
| 88 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 89 | static int strbuf_addv(struct strbuf *sb, const char *fmt, va_list ap) |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 90 | { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 91 | int len, ret; |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 92 | va_list ap_saved; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 93 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 94 | if (!strbuf_avail(sb)) { |
| 95 | ret = strbuf_grow(sb, 64); |
| 96 | if (ret) |
| 97 | return ret; |
| 98 | } |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 99 | |
| 100 | va_copy(ap_saved, ap); |
Namhyung Kim | f787d95 | 2012-10-23 22:44:50 +0900 | [diff] [blame] | 101 | len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap); |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 102 | if (len < 0) { |
| 103 | va_end(ap_saved); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 104 | return len; |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 105 | } |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 106 | if (len > strbuf_avail(sb)) { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 107 | ret = strbuf_grow(sb, len); |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 108 | if (ret) { |
| 109 | va_end(ap_saved); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 110 | return ret; |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 111 | } |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 112 | len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap_saved); |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 113 | if (len > strbuf_avail(sb)) { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 114 | pr_debug("this should not happen, your vsnprintf is broken"); |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 115 | va_end(ap_saved); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 116 | return -EINVAL; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 117 | } |
| 118 | } |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 119 | va_end(ap_saved); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 120 | return strbuf_setlen(sb, sb->len + len); |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 121 | } |
| 122 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 123 | int strbuf_addf(struct strbuf *sb, const char *fmt, ...) |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 124 | { |
| 125 | va_list ap; |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 126 | int ret; |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 127 | |
| 128 | va_start(ap, fmt); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 129 | ret = strbuf_addv(sb, fmt, ap); |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 130 | va_end(ap); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 131 | return ret; |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 132 | } |
| 133 | |
Ingo Molnar | f37a291 | 2009-07-01 12:37:06 +0200 | [diff] [blame] | 134 | ssize_t strbuf_read(struct strbuf *sb, int fd, ssize_t hint) |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 135 | { |
| 136 | size_t oldlen = sb->len; |
| 137 | size_t oldalloc = sb->alloc; |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 138 | int ret; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 139 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 140 | ret = strbuf_grow(sb, hint ? hint : 8192); |
| 141 | if (ret) |
| 142 | return ret; |
| 143 | |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 144 | for (;;) { |
| 145 | ssize_t cnt; |
| 146 | |
| 147 | cnt = read(fd, sb->buf + sb->len, sb->alloc - sb->len - 1); |
| 148 | if (cnt < 0) { |
| 149 | if (oldalloc == 0) |
| 150 | strbuf_release(sb); |
| 151 | else |
| 152 | strbuf_setlen(sb, oldlen); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 153 | return cnt; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 154 | } |
| 155 | if (!cnt) |
| 156 | break; |
| 157 | sb->len += cnt; |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 158 | ret = strbuf_grow(sb, 8192); |
| 159 | if (ret) |
| 160 | return ret; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 161 | } |
| 162 | |
| 163 | sb->buf[sb->len] = '\0'; |
| 164 | return sb->len - oldlen; |
| 165 | } |