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 | 7ed0958 | 2016-07-07 11:06:58 -0300 | [diff] [blame] | 3 | #include "util.h" |
Arnaldo Carvalho de Melo | e7f01d1 | 2012-03-14 12:29:29 -0300 | [diff] [blame] | 4 | #include <linux/kernel.h> |
Arnaldo Carvalho de Melo | a43783a | 2017-04-18 10:46:11 -0300 | [diff] [blame] | 5 | #include <errno.h> |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 6 | |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 7 | /* |
| 8 | * Used as the default ->buf value, so that people can always assume |
| 9 | * buf is non NULL and ->buf is NUL terminated even for a freshly |
| 10 | * initialized strbuf. |
| 11 | */ |
| 12 | char strbuf_slopbuf[1]; |
| 13 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 14 | int strbuf_init(struct strbuf *sb, ssize_t hint) |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 15 | { |
| 16 | sb->alloc = sb->len = 0; |
| 17 | sb->buf = strbuf_slopbuf; |
| 18 | if (hint) |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 19 | return strbuf_grow(sb, hint); |
| 20 | return 0; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 21 | } |
| 22 | |
| 23 | void strbuf_release(struct strbuf *sb) |
| 24 | { |
| 25 | if (sb->alloc) { |
Arnaldo Carvalho de Melo | 74cf249 | 2013-12-27 16:55:14 -0300 | [diff] [blame] | 26 | zfree(&sb->buf); |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 27 | strbuf_init(sb, 0); |
| 28 | } |
| 29 | } |
| 30 | |
| 31 | char *strbuf_detach(struct strbuf *sb, size_t *sz) |
| 32 | { |
| 33 | char *res = sb->alloc ? sb->buf : NULL; |
| 34 | if (sz) |
| 35 | *sz = sb->len; |
| 36 | strbuf_init(sb, 0); |
| 37 | return res; |
| 38 | } |
| 39 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 40 | int strbuf_grow(struct strbuf *sb, size_t extra) |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 41 | { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 42 | char *buf; |
| 43 | size_t nr = sb->len + extra + 1; |
| 44 | |
| 45 | if (nr < sb->alloc) |
| 46 | return 0; |
| 47 | |
| 48 | if (nr <= sb->len) |
| 49 | return -E2BIG; |
| 50 | |
| 51 | if (alloc_nr(sb->alloc) > nr) |
| 52 | nr = alloc_nr(sb->alloc); |
| 53 | |
| 54 | /* |
| 55 | * Note that sb->buf == strbuf_slopbuf if sb->alloc == 0, and it is |
| 56 | * a static variable. Thus we have to avoid passing it to realloc. |
| 57 | */ |
| 58 | buf = realloc(sb->alloc ? sb->buf : NULL, nr * sizeof(*buf)); |
| 59 | if (!buf) |
| 60 | return -ENOMEM; |
| 61 | |
| 62 | sb->buf = buf; |
| 63 | sb->alloc = nr; |
| 64 | return 0; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 65 | } |
| 66 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 67 | int strbuf_addch(struct strbuf *sb, int c) |
Arnaldo Carvalho de Melo | 0741208 | 2016-03-23 16:56:56 -0300 | [diff] [blame] | 68 | { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 69 | int ret = strbuf_grow(sb, 1); |
| 70 | if (ret) |
| 71 | return ret; |
| 72 | |
Arnaldo Carvalho de Melo | 0741208 | 2016-03-23 16:56:56 -0300 | [diff] [blame] | 73 | sb->buf[sb->len++] = c; |
| 74 | sb->buf[sb->len] = '\0'; |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 75 | return 0; |
Arnaldo Carvalho de Melo | 0741208 | 2016-03-23 16:56:56 -0300 | [diff] [blame] | 76 | } |
| 77 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 78 | int strbuf_add(struct strbuf *sb, const void *data, size_t len) |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 79 | { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 80 | int ret = strbuf_grow(sb, len); |
| 81 | if (ret) |
| 82 | return ret; |
| 83 | |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 84 | memcpy(sb->buf + sb->len, data, len); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 85 | return strbuf_setlen(sb, sb->len + len); |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 86 | } |
| 87 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 88 | 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] | 89 | { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 90 | int len, ret; |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 91 | va_list ap_saved; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 92 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 93 | if (!strbuf_avail(sb)) { |
| 94 | ret = strbuf_grow(sb, 64); |
| 95 | if (ret) |
| 96 | return ret; |
| 97 | } |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 98 | |
| 99 | va_copy(ap_saved, ap); |
Namhyung Kim | f787d95 | 2012-10-23 22:44:50 +0900 | [diff] [blame] | 100 | len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap); |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 101 | if (len < 0) { |
| 102 | va_end(ap_saved); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 103 | return len; |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 104 | } |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 105 | if (len > strbuf_avail(sb)) { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 106 | ret = strbuf_grow(sb, len); |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 107 | if (ret) { |
| 108 | va_end(ap_saved); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 109 | return ret; |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 110 | } |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 111 | 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] | 112 | if (len > strbuf_avail(sb)) { |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 113 | pr_debug("this should not happen, your vsnprintf is broken"); |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 114 | va_end(ap_saved); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 115 | return -EINVAL; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 116 | } |
| 117 | } |
Sanskriti Sharma | ce49d84 | 2018-10-02 10:29:10 -0400 | [diff] [blame] | 118 | va_end(ap_saved); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 119 | return strbuf_setlen(sb, sb->len + len); |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 120 | } |
| 121 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 122 | int strbuf_addf(struct strbuf *sb, const char *fmt, ...) |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 123 | { |
| 124 | va_list ap; |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 125 | int ret; |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 126 | |
| 127 | va_start(ap, fmt); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 128 | ret = strbuf_addv(sb, fmt, ap); |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 129 | va_end(ap); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 130 | return ret; |
Namhyung Kim | c711836 | 2015-10-25 00:49:27 +0900 | [diff] [blame] | 131 | } |
| 132 | |
Ingo Molnar | f37a291 | 2009-07-01 12:37:06 +0200 | [diff] [blame] | 133 | ssize_t strbuf_read(struct strbuf *sb, int fd, ssize_t hint) |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 134 | { |
| 135 | size_t oldlen = sb->len; |
| 136 | size_t oldalloc = sb->alloc; |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 137 | int ret; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 138 | |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 139 | ret = strbuf_grow(sb, hint ? hint : 8192); |
| 140 | if (ret) |
| 141 | return ret; |
| 142 | |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 143 | for (;;) { |
| 144 | ssize_t cnt; |
| 145 | |
| 146 | cnt = read(fd, sb->buf + sb->len, sb->alloc - sb->len - 1); |
| 147 | if (cnt < 0) { |
| 148 | if (oldalloc == 0) |
| 149 | strbuf_release(sb); |
| 150 | else |
| 151 | strbuf_setlen(sb, oldlen); |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 152 | return cnt; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 153 | } |
| 154 | if (!cnt) |
| 155 | break; |
| 156 | sb->len += cnt; |
Masami Hiramatsu | 5cea57f | 2016-05-10 14:46:58 +0900 | [diff] [blame] | 157 | ret = strbuf_grow(sb, 8192); |
| 158 | if (ret) |
| 159 | return ret; |
Ingo Molnar | 0780060 | 2009-04-20 15:00:56 +0200 | [diff] [blame] | 160 | } |
| 161 | |
| 162 | sb->buf[sb->len] = '\0'; |
| 163 | return sb->len - oldlen; |
| 164 | } |