diff options
Diffstat (limited to 'src/libsystemd-basic/src/string-util.c')
-rw-r--r-- | src/libsystemd-basic/src/string-util.c | 855 |
1 files changed, 855 insertions, 0 deletions
diff --git a/src/libsystemd-basic/src/string-util.c b/src/libsystemd-basic/src/string-util.c new file mode 100644 index 0000000000..6d65067239 --- /dev/null +++ b/src/libsystemd-basic/src/string-util.c @@ -0,0 +1,855 @@ +/*** + This file is part of systemd. + + Copyright 2010 Lennart Poettering + + systemd 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. + + systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <errno.h> +#include <stdarg.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> + +#include "systemd-basic/alloc-util.h" +#include "systemd-basic/gunicode.h" +#include "systemd-basic/macro.h" +#include "systemd-basic/string-util.h" +#include "systemd-basic/utf8.h" +#include "systemd-basic/util.h" + +int strcmp_ptr(const char *a, const char *b) { + + /* Like strcmp(), but tries to make sense of NULL pointers */ + if (a && b) + return strcmp(a, b); + + if (!a && b) + return -1; + + if (a && !b) + return 1; + + return 0; +} + +char* endswith(const char *s, const char *postfix) { + size_t sl, pl; + + assert(s); + assert(postfix); + + sl = strlen(s); + pl = strlen(postfix); + + if (pl == 0) + return (char*) s + sl; + + if (sl < pl) + return NULL; + + if (memcmp(s + sl - pl, postfix, pl) != 0) + return NULL; + + return (char*) s + sl - pl; +} + +char* endswith_no_case(const char *s, const char *postfix) { + size_t sl, pl; + + assert(s); + assert(postfix); + + sl = strlen(s); + pl = strlen(postfix); + + if (pl == 0) + return (char*) s + sl; + + if (sl < pl) + return NULL; + + if (strcasecmp(s + sl - pl, postfix) != 0) + return NULL; + + return (char*) s + sl - pl; +} + +char* first_word(const char *s, const char *word) { + size_t sl, wl; + const char *p; + + assert(s); + assert(word); + + /* Checks if the string starts with the specified word, either + * followed by NUL or by whitespace. Returns a pointer to the + * NUL or the first character after the whitespace. */ + + sl = strlen(s); + wl = strlen(word); + + if (sl < wl) + return NULL; + + if (wl == 0) + return (char*) s; + + if (memcmp(s, word, wl) != 0) + return NULL; + + p = s + wl; + if (*p == 0) + return (char*) p; + + if (!strchr(WHITESPACE, *p)) + return NULL; + + p += strspn(p, WHITESPACE); + return (char*) p; +} + +static size_t strcspn_escaped(const char *s, const char *reject) { + bool escaped = false; + int n; + + for (n=0; s[n]; n++) { + if (escaped) + escaped = false; + else if (s[n] == '\\') + escaped = true; + else if (strchr(reject, s[n])) + break; + } + + /* if s ends in \, return index of previous char */ + return n - escaped; +} + +/* Split a string into words. */ +const char* split(const char **state, size_t *l, const char *separator, bool quoted) { + const char *current; + + current = *state; + + if (!*current) { + assert(**state == '\0'); + return NULL; + } + + current += strspn(current, separator); + if (!*current) { + *state = current; + return NULL; + } + + if (quoted && strchr("\'\"", *current)) { + char quotechars[2] = {*current, '\0'}; + + *l = strcspn_escaped(current + 1, quotechars); + if (current[*l + 1] == '\0' || current[*l + 1] != quotechars[0] || + (current[*l + 2] && !strchr(separator, current[*l + 2]))) { + /* right quote missing or garbage at the end */ + *state = current; + return NULL; + } + *state = current++ + *l + 2; + } else if (quoted) { + *l = strcspn_escaped(current, separator); + if (current[*l] && !strchr(separator, current[*l])) { + /* unfinished escape */ + *state = current; + return NULL; + } + *state = current + *l; + } else { + *l = strcspn(current, separator); + *state = current + *l; + } + + return current; +} + +char *strnappend(const char *s, const char *suffix, size_t b) { + size_t a; + char *r; + + if (!s && !suffix) + return strdup(""); + + if (!s) + return strndup(suffix, b); + + if (!suffix) + return strdup(s); + + assert(s); + assert(suffix); + + a = strlen(s); + if (b > ((size_t) -1) - a) + return NULL; + + r = new(char, a+b+1); + if (!r) + return NULL; + + memcpy(r, s, a); + memcpy(r+a, suffix, b); + r[a+b] = 0; + + return r; +} + +char *strappend(const char *s, const char *suffix) { + return strnappend(s, suffix, suffix ? strlen(suffix) : 0); +} + +char *strjoin(const char *x, ...) { + va_list ap; + size_t l; + char *r, *p; + + va_start(ap, x); + + if (x) { + l = strlen(x); + + for (;;) { + const char *t; + size_t n; + + t = va_arg(ap, const char *); + if (!t) + break; + + n = strlen(t); + if (n > ((size_t) -1) - l) { + va_end(ap); + return NULL; + } + + l += n; + } + } else + l = 0; + + va_end(ap); + + r = new(char, l+1); + if (!r) + return NULL; + + if (x) { + p = stpcpy(r, x); + + va_start(ap, x); + + for (;;) { + const char *t; + + t = va_arg(ap, const char *); + if (!t) + break; + + p = stpcpy(p, t); + } + + va_end(ap); + } else + r[0] = 0; + + return r; +} + +char *strstrip(char *s) { + char *e; + + /* Drops trailing whitespace. Modifies the string in + * place. Returns pointer to first non-space character */ + + s += strspn(s, WHITESPACE); + + for (e = strchr(s, 0); e > s; e --) + if (!strchr(WHITESPACE, e[-1])) + break; + + *e = 0; + + return s; +} + +char *delete_chars(char *s, const char *bad) { + char *f, *t; + + /* Drops all whitespace, regardless where in the string */ + + for (f = s, t = s; *f; f++) { + if (strchr(bad, *f)) + continue; + + *(t++) = *f; + } + + *t = 0; + + return s; +} + +char *truncate_nl(char *s) { + assert(s); + + s[strcspn(s, NEWLINE)] = 0; + return s; +} + +char ascii_tolower(char x) { + + if (x >= 'A' && x <= 'Z') + return x - 'A' + 'a'; + + return x; +} + +char *ascii_strlower(char *t) { + char *p; + + assert(t); + + for (p = t; *p; p++) + *p = ascii_tolower(*p); + + return t; +} + +char *ascii_strlower_n(char *t, size_t n) { + size_t i; + + if (n <= 0) + return t; + + for (i = 0; i < n; i++) + t[i] = ascii_tolower(t[i]); + + return t; +} + +int ascii_strcasecmp_n(const char *a, const char *b, size_t n) { + + for (; n > 0; a++, b++, n--) { + int x, y; + + x = (int) (uint8_t) ascii_tolower(*a); + y = (int) (uint8_t) ascii_tolower(*b); + + if (x != y) + return x - y; + } + + return 0; +} + +int ascii_strcasecmp_nn(const char *a, size_t n, const char *b, size_t m) { + int r; + + r = ascii_strcasecmp_n(a, b, MIN(n, m)); + if (r != 0) + return r; + + if (n < m) + return -1; + else if (n > m) + return 1; + else + return 0; +} + +bool chars_intersect(const char *a, const char *b) { + const char *p; + + /* Returns true if any of the chars in a are in b. */ + for (p = a; *p; p++) + if (strchr(b, *p)) + return true; + + return false; +} + +bool string_has_cc(const char *p, const char *ok) { + const char *t; + + assert(p); + + /* + * Check if a string contains control characters. If 'ok' is + * non-NULL it may be a string containing additional CCs to be + * considered OK. + */ + + for (t = p; *t; t++) { + if (ok && strchr(ok, *t)) + continue; + + if (*t > 0 && *t < ' ') + return true; + + if (*t == 127) + return true; + } + + return false; +} + +static char *ascii_ellipsize_mem(const char *s, size_t old_length, size_t new_length, unsigned percent) { + size_t x; + char *r; + + assert(s); + assert(percent <= 100); + assert(new_length >= 3); + + if (old_length <= 3 || old_length <= new_length) + return strndup(s, old_length); + + r = new0(char, new_length+1); + if (!r) + return NULL; + + x = (new_length * percent) / 100; + + if (x > new_length - 3) + x = new_length - 3; + + memcpy(r, s, x); + r[x] = '.'; + r[x+1] = '.'; + r[x+2] = '.'; + memcpy(r + x + 3, + s + old_length - (new_length - x - 3), + new_length - x - 3); + + return r; +} + +char *ellipsize_mem(const char *s, size_t old_length, size_t new_length, unsigned percent) { + size_t x; + char *e; + const char *i, *j; + unsigned k, len, len2; + int r; + + assert(s); + assert(percent <= 100); + assert(new_length >= 3); + + /* if no multibyte characters use ascii_ellipsize_mem for speed */ + if (ascii_is_valid(s)) + return ascii_ellipsize_mem(s, old_length, new_length, percent); + + if (old_length <= 3 || old_length <= new_length) + return strndup(s, old_length); + + x = (new_length * percent) / 100; + + if (x > new_length - 3) + x = new_length - 3; + + k = 0; + for (i = s; k < x && i < s + old_length; i = utf8_next_char(i)) { + char32_t c; + + r = utf8_encoded_to_unichar(i, &c); + if (r < 0) + return NULL; + k += unichar_iswide(c) ? 2 : 1; + } + + if (k > x) /* last character was wide and went over quota */ + x++; + + for (j = s + old_length; k < new_length && j > i; ) { + char32_t c; + + j = utf8_prev_char(j); + r = utf8_encoded_to_unichar(j, &c); + if (r < 0) + return NULL; + k += unichar_iswide(c) ? 2 : 1; + } + assert(i <= j); + + /* we don't actually need to ellipsize */ + if (i == j) + return memdup(s, old_length + 1); + + /* make space for ellipsis */ + j = utf8_next_char(j); + + len = i - s; + len2 = s + old_length - j; + e = new(char, len + 3 + len2 + 1); + if (!e) + return NULL; + + /* + printf("old_length=%zu new_length=%zu x=%zu len=%u len2=%u k=%u\n", + old_length, new_length, x, len, len2, k); + */ + + memcpy(e, s, len); + e[len] = 0xe2; /* tri-dot ellipsis: … */ + e[len + 1] = 0x80; + e[len + 2] = 0xa6; + + memcpy(e + len + 3, j, len2 + 1); + + return e; +} + +char *ellipsize(const char *s, size_t length, unsigned percent) { + return ellipsize_mem(s, strlen(s), length, percent); +} + +bool nulstr_contains(const char*nulstr, const char *needle) { + const char *i; + + if (!nulstr) + return false; + + NULSTR_FOREACH(i, nulstr) + if (streq(i, needle)) + return true; + + return false; +} + +char* strshorten(char *s, size_t l) { + assert(s); + + if (l < strlen(s)) + s[l] = 0; + + return s; +} + +char *strreplace(const char *text, const char *old_string, const char *new_string) { + const char *f; + char *t, *r; + size_t l, old_len, new_len; + + assert(text); + assert(old_string); + assert(new_string); + + old_len = strlen(old_string); + new_len = strlen(new_string); + + l = strlen(text); + r = new(char, l+1); + if (!r) + return NULL; + + f = text; + t = r; + while (*f) { + char *a; + size_t d, nl; + + if (!startswith(f, old_string)) { + *(t++) = *(f++); + continue; + } + + d = t - r; + nl = l - old_len + new_len; + a = realloc(r, nl + 1); + if (!a) + goto oom; + + l = nl; + r = a; + t = r + d; + + t = stpcpy(t, new_string); + f += old_len; + } + + *t = 0; + return r; + +oom: + free(r); + return NULL; +} + +char *strip_tab_ansi(char **ibuf, size_t *_isz) { + const char *i, *begin = NULL; + enum { + STATE_OTHER, + STATE_ESCAPE, + STATE_BRACKET + } state = STATE_OTHER; + char *obuf = NULL; + size_t osz = 0, isz; + FILE *f; + + assert(ibuf); + assert(*ibuf); + + /* Strips ANSI color and replaces TABs by 8 spaces */ + + isz = _isz ? *_isz : strlen(*ibuf); + + f = open_memstream(&obuf, &osz); + if (!f) + return NULL; + + for (i = *ibuf; i < *ibuf + isz + 1; i++) { + + switch (state) { + + case STATE_OTHER: + if (i >= *ibuf + isz) /* EOT */ + break; + else if (*i == '\x1B') + state = STATE_ESCAPE; + else if (*i == '\t') + fputs(" ", f); + else + fputc(*i, f); + break; + + case STATE_ESCAPE: + if (i >= *ibuf + isz) { /* EOT */ + fputc('\x1B', f); + break; + } else if (*i == '[') { + state = STATE_BRACKET; + begin = i + 1; + } else { + fputc('\x1B', f); + fputc(*i, f); + state = STATE_OTHER; + } + + break; + + case STATE_BRACKET: + + if (i >= *ibuf + isz || /* EOT */ + (!(*i >= '0' && *i <= '9') && *i != ';' && *i != 'm')) { + fputc('\x1B', f); + fputc('[', f); + state = STATE_OTHER; + i = begin-1; + } else if (*i == 'm') + state = STATE_OTHER; + break; + } + } + + if (ferror(f)) { + fclose(f); + free(obuf); + return NULL; + } + + fclose(f); + + free(*ibuf); + *ibuf = obuf; + + if (_isz) + *_isz = osz; + + return obuf; +} + +char *strextend(char **x, ...) { + va_list ap; + size_t f, l; + char *r, *p; + + assert(x); + + l = f = *x ? strlen(*x) : 0; + + va_start(ap, x); + for (;;) { + const char *t; + size_t n; + + t = va_arg(ap, const char *); + if (!t) + break; + + n = strlen(t); + if (n > ((size_t) -1) - l) { + va_end(ap); + return NULL; + } + + l += n; + } + va_end(ap); + + r = realloc(*x, l+1); + if (!r) + return NULL; + + p = r + f; + + va_start(ap, x); + for (;;) { + const char *t; + + t = va_arg(ap, const char *); + if (!t) + break; + + p = stpcpy(p, t); + } + va_end(ap); + + *p = 0; + *x = r; + + return r + l; +} + +char *strrep(const char *s, unsigned n) { + size_t l; + char *r, *p; + unsigned i; + + assert(s); + + l = strlen(s); + p = r = malloc(l * n + 1); + if (!r) + return NULL; + + for (i = 0; i < n; i++) + p = stpcpy(p, s); + + *p = 0; + return r; +} + +int split_pair(const char *s, const char *sep, char **l, char **r) { + char *x, *a, *b; + + assert(s); + assert(sep); + assert(l); + assert(r); + + if (isempty(sep)) + return -EINVAL; + + x = strstr(s, sep); + if (!x) + return -EINVAL; + + a = strndup(s, x - s); + if (!a) + return -ENOMEM; + + b = strdup(x + strlen(sep)); + if (!b) { + free(a); + return -ENOMEM; + } + + *l = a; + *r = b; + + return 0; +} + +int free_and_strdup(char **p, const char *s) { + char *t; + + assert(p); + + /* Replaces a string pointer with an strdup()ed new string, + * possibly freeing the old one. */ + + if (streq_ptr(*p, s)) + return 0; + + if (s) { + t = strdup(s); + if (!t) + return -ENOMEM; + } else + t = NULL; + + free(*p); + *p = t; + + return 1; +} + +#pragma GCC push_options +#pragma GCC optimize("O0") + +void* memory_erase(void *p, size_t l) { + volatile uint8_t* x = (volatile uint8_t*) p; + + /* This basically does what memset() does, but hopefully isn't + * optimized away by the compiler. One of those days, when + * glibc learns memset_s() we should replace this call by + * memset_s(), but until then this has to do. */ + + for (; l > 0; l--) + *(x++) = 'x'; + + return p; +} + +#pragma GCC pop_options + +char* string_erase(char *x) { + + if (!x) + return NULL; + + /* A delicious drop of snake-oil! To be called on memory where + * we stored passphrases or so, after we used them. */ + + return memory_erase(x, strlen(x)); +} + +char *string_free_erase(char *s) { + return mfree(string_erase(s)); +} + +bool string_is_safe(const char *p) { + const char *t; + + if (!p) + return false; + + for (t = p; *t; t++) { + if (*t > 0 && *t < ' ') /* no control characters */ + return false; + + if (strchr(QUOTES "\\\x7f", *t)) + return false; + } + + return true; +} |