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Diffstat (limited to 'library/escape.c')
| -rw-r--r-- | library/escape.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/library/escape.c b/library/escape.c new file mode 100644 index 0000000..f988672 --- /dev/null +++ b/library/escape.c @@ -0,0 +1,157 @@ +/* + * escape.c - printing handling + * + * Copyright © 2011-2023 Jim Warner <james.warner@comcast.net> + * Copyright © 2016-2023 Craig Small <csmall@dropbear.xyz> + * Copyright © 1998-2005 Albert Cahalan + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <limits.h> +#include <stdio.h> +#include <string.h> + +#include "escape.h" +#include "readproc.h" +#include "nls.h" + +#define SECURE_ESCAPE_ARGS(dst, bytes) do { \ + if ((bytes) <= 0) return 0; \ + *(dst) = '\0'; \ + if ((bytes) >= INT_MAX) return 0; \ +} while (0) + +static const char UTF_tab[] = { + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 0x00 - 0x0F + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 0x10 - 0x1F + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 0x20 - 0x2F + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 0x30 - 0x3F + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 0x40 - 0x4F + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 0x50 - 0x5F + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 0x60 - 0x6F + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 0x70 - 0x7F + -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1, // 0x80 - 0x8F + -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1, // 0x90 - 0x9F + -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1, // 0xA0 - 0xAF + -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1, // 0xB0 - 0xBF + -1,-1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, // 0xC0 - 0xCF + 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, // 0xD0 - 0xDF + 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, // 0xE0 - 0xEF + 4, 4, 4, 4, 4,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1, // 0xF0 - 0xFF +}; + +static const unsigned char ESC_tab[] = { + "@..............................." // 0x00 - 0x1F + "||||||||||||||||||||||||||||||||" // 0x20 - 0x3F + "||||||||||||||||||||||||||||||||" // 0x40 - 0x5f + "|||||||||||||||||||||||||||||||." // 0x60 - 0x7F + "????????????????????????????????" // 0x80 - 0x9F + "????????????????????????????????" // 0xA0 - 0xBF + "????????????????????????????????" // 0xC0 - 0xDF + "????????????????????????????????" // 0xE0 - 0xFF +}; + +static inline void esc_all (unsigned char *str) { + unsigned char c; + + // if bad locale/corrupt str, replace non-printing stuff + while (*str) { + if ((c = ESC_tab[*str]) != '|') + *str = c; + ++str; + } +} + +static inline void esc_ctl (unsigned char *str, int len) { + #define setQ { *str = '?'; n = 1; goto next_up; } + int i, n, x; + + for (i = 0; i < len; ) { + n = UTF_tab[*str]; + /* even with a proper locale, strings might be corrupt or we + might encounter one of those 32 unicode multibyte control + characters which begin at U+0080 (0xc280) */ + if (n < 0 || i + n > len + || (*str == 0xc2 && str[1] >= 0x80 && str[1] <= 0x9f)) { + setQ + } + /* let's validate those utf-8 continuation bytes too, all of + which must take the binary form of 10xxxxxx */ + for (x = 1; x < n; x++) { + if (str[x] < 0x80 || str[x] > 0xbf) { + setQ + } + } + // and eliminate those non-printing control characters + if (*str < 0x20 || *str == 0x7f) + *str = '?'; +next_up: + str += n; + i += n; + } + #undef setQ +} + +int escape_str (char *dst, const char *src, int bufsize) { + static __thread int utf_sw = 0; + int n; + + if (utf_sw == 0) { + char *enc = nl_langinfo(CODESET); + utf_sw = enc && strcasecmp(enc, "UTF-8") == 0 ? 1 : -1; + } + SECURE_ESCAPE_ARGS(dst, bufsize); + n = snprintf(dst, bufsize, "%s", src); + if (n < 0) { + *dst = '\0'; + return 0; + } + if (n >= bufsize) n = bufsize-1; + if (utf_sw < 0) + esc_all((unsigned char *)dst); + else + esc_ctl((unsigned char *)dst, n); + return n; +} + +int escape_command (char *outbuf, const proc_t *pp, int bytes, unsigned flags) { + int overhead = 0; + int end = 0; + + if (flags & ESC_BRACKETS) + overhead += 2; + if (flags & ESC_DEFUNCT) { + if (pp->state == 'Z') overhead += 10; // chars in " <defunct>" + else flags &= ~ESC_DEFUNCT; + } + if (overhead + 1 >= bytes) { + // if no room for even one byte of the command name + outbuf[0] = '\0'; + return 0; + } + if (flags & ESC_BRACKETS) + outbuf[end++] = '['; + end += escape_str(outbuf+end, pp->cmd, bytes-overhead); + // we want "[foo] <defunct>", not "[foo <defunct>]" + if (flags & ESC_BRACKETS) + outbuf[end++] = ']'; + if (flags & ESC_DEFUNCT) { + memcpy(outbuf+end, " <defunct>", 10); + end += 10; + } + outbuf[end] = '\0'; + return end; // bytes, not including the NUL +} |