diff options
Diffstat (limited to 'lib/util/lbuf.c')
-rw-r--r-- | lib/util/lbuf.c | 448 |
1 files changed, 448 insertions, 0 deletions
diff --git a/lib/util/lbuf.c b/lib/util/lbuf.c new file mode 100644 index 0000000..018fa5e --- /dev/null +++ b/lib/util/lbuf.c @@ -0,0 +1,448 @@ +/* + * SPDX-License-Identifier: ISC + * + * Copyright (c) 2007-2015, 2023 Todd C. Miller <Todd.Miller@sudo.ws> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* + * This is an open source non-commercial project. Dear PVS-Studio, please check it. + * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com + */ + +#include <config.h> + +#include <stdlib.h> +#include <string.h> +#include <ctype.h> +#include <errno.h> + +#include "sudo_compat.h" +#include "sudo_debug.h" +#include "sudo_lbuf.h" +#include "sudo_util.h" + +void +sudo_lbuf_init_v1(struct sudo_lbuf *lbuf, sudo_lbuf_output_t output, + int indent, const char *continuation, int cols) +{ + debug_decl(sudo_lbuf_init, SUDO_DEBUG_UTIL); + + lbuf->output = output; + lbuf->continuation = continuation; + lbuf->indent = indent; + lbuf->cols = cols; + lbuf->error = 0; + lbuf->len = 0; + lbuf->size = 0; + lbuf->buf = NULL; + + debug_return; +} + +void +sudo_lbuf_destroy_v1(struct sudo_lbuf *lbuf) +{ + debug_decl(sudo_lbuf_destroy, SUDO_DEBUG_UTIL); + + free(lbuf->buf); + lbuf->error = 0; + lbuf->len = 0; + lbuf->size = 0; + lbuf->buf = NULL; + + debug_return; +} + +static bool +sudo_lbuf_expand(struct sudo_lbuf *lbuf, unsigned int extra) +{ + debug_decl(sudo_lbuf_expand, SUDO_DEBUG_UTIL); + + if (lbuf->len + extra + 1 <= lbuf->len) { + errno = ENOMEM; + sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO, + "integer overflow updating lbuf->len"); + lbuf->error = 1; + debug_return_bool(false); + } + + if (lbuf->len + extra + 1 > lbuf->size) { + unsigned int new_size = sudo_pow2_roundup(lbuf->len + extra + 1); + char *new_buf; + + if (new_size < lbuf->size) { + errno = ENOMEM; + sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO, + "integer overflow updating lbuf->size"); + lbuf->error = 1; + debug_return_bool(false); + } + if (new_size < 1024) + new_size = 1024; + if ((new_buf = realloc(lbuf->buf, new_size)) == NULL) { + sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO, + "unable to allocate memory"); + lbuf->error = 1; + debug_return_bool(false); + } + lbuf->buf = new_buf; + lbuf->size = new_size; + } + debug_return_bool(true); +} + +/* + * Escape a character in octal form (#0n) and store it as a string + * in buf, which must have at least 6 bytes available. + * Returns the length of buf, not counting the terminating NUL byte. + */ +static int +escape(unsigned char ch, char *buf) +{ + const int len = ch < 0100 ? (ch < 010 ? 3 : 4) : 5; + + /* Work backwards from the least significant digit to most significant. */ + switch (len) { + case 5: + buf[4] = (ch & 7) + '0'; + ch >>= 3; + FALLTHROUGH; + case 4: + buf[3] = (ch & 7) + '0'; + ch >>= 3; + FALLTHROUGH; + case 3: + buf[2] = (ch & 7) + '0'; + buf[1] = '0'; + buf[0] = '#'; + break; + } + buf[len] = '\0'; + + return len; +} + +/* + * Parse the format and append strings, only %s and %% escapes are supported. + * Any non-printable characters are escaped in octal as #0nn. + */ +bool +sudo_lbuf_append_esc_v1(struct sudo_lbuf *lbuf, int flags, const char *fmt, ...) +{ + unsigned int saved_len = lbuf->len; + bool ret = false; + const char *s; + va_list ap; + debug_decl(sudo_lbuf_append_esc, SUDO_DEBUG_UTIL); + + if (sudo_lbuf_error(lbuf)) + debug_return_bool(false); + +#define should_escape(ch) \ + ((ISSET(flags, LBUF_ESC_CNTRL) && iscntrl((unsigned char)ch)) || \ + (ISSET(flags, LBUF_ESC_BLANK) && isblank((unsigned char)ch))) +#define should_quote(ch) \ + (ISSET(flags, LBUF_ESC_QUOTE) && (ch == '\'' || ch == '\\')) + + va_start(ap, fmt); + while (*fmt != '\0') { + if (fmt[0] == '%' && fmt[1] == 's') { + if ((s = va_arg(ap, char *)) == NULL) + s = "(NULL)"; + while (*s != '\0') { + if (should_escape(*s)) { + if (!sudo_lbuf_expand(lbuf, sizeof("#0177") - 1)) + goto done; + lbuf->len += escape(*s++, lbuf->buf + lbuf->len); + continue; + } + if (should_quote(*s)) { + if (!sudo_lbuf_expand(lbuf, 2)) + goto done; + lbuf->buf[lbuf->len++] = '\\'; + lbuf->buf[lbuf->len++] = *s++; + continue; + } + if (!sudo_lbuf_expand(lbuf, 1)) + goto done; + lbuf->buf[lbuf->len++] = *s++; + } + fmt += 2; + continue; + } + if (should_escape(*fmt)) { + if (!sudo_lbuf_expand(lbuf, sizeof("#0177") - 1)) + goto done; + if (*fmt == '\'') { + lbuf->buf[lbuf->len++] = '\\'; + lbuf->buf[lbuf->len++] = *fmt++; + } else { + lbuf->len += escape(*fmt++, lbuf->buf + lbuf->len); + } + continue; + } + if (!sudo_lbuf_expand(lbuf, 1)) + goto done; + lbuf->buf[lbuf->len++] = *fmt++; + } + ret = true; + +done: + if (!ret) + lbuf->len = saved_len; + if (lbuf->size != 0) + lbuf->buf[lbuf->len] = '\0'; + va_end(ap); + + debug_return_bool(ret); +} + +/* + * Parse the format and append strings, only %s and %% escapes are supported. + * Any characters in set are quoted with a backslash. + */ +bool +sudo_lbuf_append_quoted_v1(struct sudo_lbuf *lbuf, const char *set, const char *fmt, ...) +{ + unsigned int saved_len = lbuf->len; + bool ret = false; + const char *cp, *s; + va_list ap; + int len; + debug_decl(sudo_lbuf_append_quoted, SUDO_DEBUG_UTIL); + + if (sudo_lbuf_error(lbuf)) + debug_return_bool(false); + + va_start(ap, fmt); + while (*fmt != '\0') { + if (fmt[0] == '%' && fmt[1] == 's') { + if ((s = va_arg(ap, char *)) == NULL) + s = "(NULL)"; + while ((cp = strpbrk(s, set)) != NULL) { + len = (int)(cp - s); + if (!sudo_lbuf_expand(lbuf, len + 2)) + goto done; + memcpy(lbuf->buf + lbuf->len, s, len); + lbuf->len += len; + lbuf->buf[lbuf->len++] = '\\'; + lbuf->buf[lbuf->len++] = *cp; + s = cp + 1; + } + if (*s != '\0') { + len = strlen(s); + if (!sudo_lbuf_expand(lbuf, len)) + goto done; + memcpy(lbuf->buf + lbuf->len, s, len); + lbuf->len += len; + } + fmt += 2; + continue; + } + if (!sudo_lbuf_expand(lbuf, 2)) + goto done; + if (strchr(set, *fmt) != NULL) + lbuf->buf[lbuf->len++] = '\\'; + lbuf->buf[lbuf->len++] = *fmt++; + } + ret = true; + +done: + if (!ret) + lbuf->len = saved_len; + if (lbuf->size != 0) + lbuf->buf[lbuf->len] = '\0'; + va_end(ap); + + debug_return_bool(ret); +} + +/* + * Parse the format and append strings, only %s and %% escapes are supported. + */ +bool +sudo_lbuf_append_v1(struct sudo_lbuf *lbuf, const char *fmt, ...) +{ + unsigned int saved_len = lbuf->len; + bool ret = false; + va_list ap; + const char *s; + int len; + debug_decl(sudo_lbuf_append, SUDO_DEBUG_UTIL); + + if (sudo_lbuf_error(lbuf)) + debug_return_bool(false); + + va_start(ap, fmt); + while (*fmt != '\0') { + if (fmt[0] == '%' && fmt[1] == 's') { + if ((s = va_arg(ap, char *)) == NULL) + s = "(NULL)"; + len = strlen(s); + if (!sudo_lbuf_expand(lbuf, len)) + goto done; + memcpy(lbuf->buf + lbuf->len, s, len); + lbuf->len += len; + fmt += 2; + continue; + } + if (!sudo_lbuf_expand(lbuf, 1)) + goto done; + lbuf->buf[lbuf->len++] = *fmt++; + } + ret = true; + +done: + if (!ret) + lbuf->len = saved_len; + if (lbuf->size != 0) + lbuf->buf[lbuf->len] = '\0'; + va_end(ap); + + debug_return_bool(ret); +} + +/* XXX - check output function return value */ +static void +sudo_lbuf_println(struct sudo_lbuf *lbuf, char *line, int len) +{ + char *cp, save; + int i, have, contlen = 0; + int indent = lbuf->indent; + bool is_comment = false; + debug_decl(sudo_lbuf_println, SUDO_DEBUG_UTIL); + + /* Comment lines don't use continuation and only indent is for "# " */ + if (line[0] == '#' && isblank((unsigned char)line[1])) { + is_comment = true; + indent = 2; + } + if (lbuf->continuation != NULL && !is_comment) + contlen = strlen(lbuf->continuation); + + /* + * Print the buffer, splitting the line as needed on a word + * boundary. + */ + cp = line; + have = lbuf->cols; + while (cp != NULL && *cp != '\0') { + char *ep = NULL; + int need = len - (int)(cp - line); + + if (need > have) { + have -= contlen; /* subtract for continuation char */ + if ((ep = memrchr(cp, ' ', have)) == NULL) + ep = memchr(cp + have, ' ', need - have); + if (ep != NULL) + need = (int)(ep - cp); + } + if (cp != line) { + if (is_comment) { + lbuf->output("# "); + } else { + /* indent continued lines */ + /* XXX - build up string instead? */ + for (i = 0; i < indent; i++) + lbuf->output(" "); + } + } + /* NUL-terminate cp for the output function and restore afterwards */ + save = cp[need]; + cp[need] = '\0'; + lbuf->output(cp); + cp[need] = save; + cp = ep; + + /* + * If there is more to print, reset have, incremement cp past + * the whitespace, and print a line continuaton char if needed. + */ + if (cp != NULL) { + have = lbuf->cols - indent; + ep = line + len; + while (cp < ep && isblank((unsigned char)*cp)) { + cp++; + } + if (contlen) + lbuf->output(lbuf->continuation); + } + lbuf->output("\n"); + } + + debug_return; +} + +/* + * Print the buffer with word wrap based on the tty width. + * The lbuf is reset on return. + * XXX - check output function return value + */ +void +sudo_lbuf_print_v1(struct sudo_lbuf *lbuf) +{ + char *cp, *ep; + int len; + debug_decl(sudo_lbuf_print, SUDO_DEBUG_UTIL); + + if (lbuf->buf == NULL || lbuf->len == 0) + goto done; + + /* For very small widths just give up... */ + len = lbuf->continuation ? strlen(lbuf->continuation) : 0; + if (lbuf->cols <= lbuf->indent + len + 20) { + lbuf->buf[lbuf->len] = '\0'; + lbuf->output(lbuf->buf); + if (lbuf->buf[lbuf->len - 1] != '\n') + lbuf->output("\n"); + goto done; + } + + /* Print each line in the buffer */ + for (cp = lbuf->buf; cp != NULL && *cp != '\0'; ) { + if (*cp == '\n') { + lbuf->output("\n"); + cp++; + } else { + len = lbuf->len - (cp - lbuf->buf); + if ((ep = memchr(cp, '\n', len)) != NULL) + len = (int)(ep - cp); + if (len) + sudo_lbuf_println(lbuf, cp, len); + cp = ep ? ep + 1 : NULL; + } + } + +done: + lbuf->len = 0; /* reset the buffer for re-use. */ + lbuf->error = 0; + + debug_return; +} + +bool +sudo_lbuf_error_v1(struct sudo_lbuf *lbuf) +{ + if (lbuf != NULL && lbuf->error != 0) + return true; + return false; +} + +void +sudo_lbuf_clearerr_v1(struct sudo_lbuf *lbuf) +{ + if (lbuf != NULL) + lbuf->error = 0; +} |