diff options
Diffstat (limited to '')
-rw-r--r-- | src/basic/string-util.c | 1099 |
1 files changed, 1099 insertions, 0 deletions
diff --git a/src/basic/string-util.c b/src/basic/string-util.c new file mode 100644 index 0000000..93917bc --- /dev/null +++ b/src/basic/string-util.c @@ -0,0 +1,1099 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <errno.h> +#include <stdarg.h> +#include <stdint.h> +#include <stdio.h> +#include <stdio_ext.h> +#include <stdlib.h> +#include <string.h> + +#include "alloc-util.h" +#include "escape.h" +#include "gunicode.h" +#include "locale-util.h" +#include "macro.h" +#include "string-util.h" +#include "terminal-util.h" +#include "utf8.h" +#include "util.h" +#include "fileio.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, SplitFlags flags) { + const char *current; + + current = *state; + + if (!*current) { + assert(**state == '\0'); + return NULL; + } + + current += strspn(current, separator); + if (!*current) { + *state = current; + return NULL; + } + + if (flags & SPLIT_QUOTES && 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 */ + if (flags & SPLIT_RELAX) { + *state = current + *l + 1 + (current[*l + 1] != '\0'); + return current + 1; + } + *state = current; + return NULL; + } + *state = current++ + *l + 2; + } else if (flags & SPLIT_QUOTES) { + *l = strcspn_escaped(current, separator); + if (current[*l] && !strchr(separator, current[*l]) && !(flags & SPLIT_RELAX)) { + /* 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, strlen_ptr(suffix)); +} + +char *strjoin_real(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) { + if (!s) + return NULL; + + /* Drops trailing whitespace. Modifies the string in place. Returns pointer to first non-space character */ + + return delete_trailing_chars(skip_leading_chars(s, WHITESPACE), WHITESPACE); +} + +char *delete_chars(char *s, const char *bad) { + char *f, *t; + + /* Drops all specified bad characters, regardless where in the string */ + + if (!s) + return NULL; + + if (!bad) + bad = WHITESPACE; + + for (f = s, t = s; *f; f++) { + if (strchr(bad, *f)) + continue; + + *(t++) = *f; + } + + *t = 0; + + return s; +} + +char *delete_trailing_chars(char *s, const char *bad) { + char *p, *c = s; + + /* Drops all specified bad characters, at the end of the string */ + + if (!s) + return NULL; + + if (!bad) + bad = WHITESPACE; + + for (p = s; *p; p++) + if (!strchr(bad, *p)) + c = p + 1; + + *c = 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_toupper(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_strupper(char *t) { + char *p; + + assert(t); + + for (p = t; *p; p++) + *p = ascii_toupper(*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; + + return CMP(n, m); +} + +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 int write_ellipsis(char *buf, bool unicode) { + if (unicode || is_locale_utf8()) { + buf[0] = 0xe2; /* tri-dot ellipsis: … */ + buf[1] = 0x80; + buf[2] = 0xa6; + } else { + buf[0] = '.'; + buf[1] = '.'; + buf[2] = '.'; + } + + return 3; +} + +static char *ascii_ellipsize_mem(const char *s, size_t old_length, size_t new_length, unsigned percent) { + size_t x, need_space, suffix_len; + char *t; + + assert(s); + assert(percent <= 100); + assert(new_length != (size_t) -1); + + if (old_length <= new_length) + return strndup(s, old_length); + + /* Special case short ellipsations */ + switch (new_length) { + + case 0: + return strdup(""); + + case 1: + if (is_locale_utf8()) + return strdup("…"); + else + return strdup("."); + + case 2: + if (!is_locale_utf8()) + return strdup(".."); + + break; + + default: + break; + } + + /* Calculate how much space the ellipsis will take up. If we are in UTF-8 mode we only need space for one + * character ("…"), otherwise for three characters ("..."). Note that in both cases we need 3 bytes of storage, + * either for the UTF-8 encoded character or for three ASCII characters. */ + need_space = is_locale_utf8() ? 1 : 3; + + t = new(char, new_length+3); + if (!t) + return NULL; + + assert(new_length >= need_space); + + x = ((new_length - need_space) * percent + 50) / 100; + assert(x <= new_length - need_space); + + memcpy(t, s, x); + write_ellipsis(t + x, false); + suffix_len = new_length - x - need_space; + memcpy(t + x + 3, s + old_length - suffix_len, suffix_len); + *(t + x + 3 + suffix_len) = '\0'; + + return t; +} + +char *ellipsize_mem(const char *s, size_t old_length, size_t new_length, unsigned percent) { + size_t x, k, len, len2; + const char *i, *j; + char *e; + int r; + + /* Note that 'old_length' refers to bytes in the string, while 'new_length' refers to character cells taken up + * on screen. This distinction doesn't matter for ASCII strings, but it does matter for non-ASCII UTF-8 + * strings. + * + * Ellipsation is done in a locale-dependent way: + * 1. If the string passed in is fully ASCII and the current locale is not UTF-8, three dots are used ("...") + * 2. Otherwise, a unicode ellipsis is used ("…") + * + * In other words: you'll get a unicode ellipsis as soon as either the string contains non-ASCII characters or + * the current locale is UTF-8. + */ + + assert(s); + assert(percent <= 100); + + if (new_length == (size_t) -1) + return strndup(s, old_length); + + if (new_length == 0) + return strdup(""); + + /* If no multibyte characters use ascii_ellipsize_mem for speed */ + if (ascii_is_valid_n(s, old_length)) + return ascii_ellipsize_mem(s, old_length, new_length, percent); + + x = ((new_length - 1) * percent) / 100; + assert(x <= new_length - 1); + + k = 0; + for (i = s; i < s + old_length; i = utf8_next_char(i)) { + char32_t c; + int w; + + r = utf8_encoded_to_unichar(i, &c); + if (r < 0) + return NULL; + + w = unichar_iswide(c) ? 2 : 1; + if (k + w <= x) + k += w; + else + break; + } + + for (j = s + old_length; j > i; ) { + char32_t c; + int w; + const char *jj; + + jj = utf8_prev_char(j); + r = utf8_encoded_to_unichar(jj, &c); + if (r < 0) + return NULL; + + w = unichar_iswide(c) ? 2 : 1; + if (k + w <= new_length) { + k += w; + j = jj; + } else + break; + } + assert(i <= j); + + /* we don't actually need to ellipsize */ + if (i == j) + return memdup_suffix0(s, old_length); + + /* make space for ellipsis, if possible */ + if (j < s + old_length) + j = utf8_next_char(j); + else if (i > s) + i = utf8_prev_char(i); + + 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); + write_ellipsis(e + len, true); + memcpy(e + len + 3, j, len2); + *(e + len + 3 + len2) = '\0'; + + return e; +} + +char *cellescape(char *buf, size_t len, const char *s) { + /* Escape and ellipsize s into buffer buf of size len. Only non-control ASCII + * characters are copied as they are, everything else is escaped. The result + * is different then if escaping and ellipsization was performed in two + * separate steps, because each sequence is either stored in full or skipped. + * + * This function should be used for logging about strings which expected to + * be plain ASCII in a safe way. + * + * An ellipsis will be used if s is too long. It was always placed at the + * very end. + */ + + size_t i = 0, last_char_width[4] = {}, k = 0, j; + + assert(len > 0); /* at least a terminating NUL */ + + for (;;) { + char four[4]; + int w; + + if (*s == 0) /* terminating NUL detected? then we are done! */ + goto done; + + w = cescape_char(*s, four); + if (i + w + 1 > len) /* This character doesn't fit into the buffer anymore? In that case let's + * ellipsize at the previous location */ + break; + + /* OK, there was space, let's add this escaped character to the buffer */ + memcpy(buf + i, four, w); + i += w; + + /* And remember its width in the ring buffer */ + last_char_width[k] = w; + k = (k + 1) % 4; + + s++; + } + + /* Ellipsation is necessary. This means we might need to truncate the string again to make space for 4 + * characters ideally, but the buffer is shorter than that in the first place take what we can get */ + for (j = 0; j < ELEMENTSOF(last_char_width); j++) { + + if (i + 4 <= len) /* nice, we reached our space goal */ + break; + + k = k == 0 ? 3 : k - 1; + if (last_char_width[k] == 0) /* bummer, we reached the beginning of the strings */ + break; + + assert(i >= last_char_width[k]); + i -= last_char_width[k]; + } + + if (i + 4 <= len) /* yay, enough space */ + i += write_ellipsis(buf + i, false); + else if (i + 3 <= len) { /* only space for ".." */ + buf[i++] = '.'; + buf[i++] = '.'; + } else if (i + 2 <= len) /* only space for a single "." */ + buf[i++] = '.'; + else + assert(i + 1 <= len); + + done: + buf[i] = '\0'; + return buf; +} + +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 (strnlen(s, l+1) > l) + s[l] = 0; + + return s; +} + +char *strreplace(const char *text, const char *old_string, const char *new_string) { + size_t l, old_len, new_len, allocated = 0; + char *t, *ret = NULL; + const char *f; + + assert(old_string); + assert(new_string); + + if (!text) + return NULL; + + old_len = strlen(old_string); + new_len = strlen(new_string); + + l = strlen(text); + if (!GREEDY_REALLOC(ret, allocated, l+1)) + return NULL; + + f = text; + t = ret; + while (*f) { + size_t d, nl; + + if (!startswith(f, old_string)) { + *(t++) = *(f++); + continue; + } + + d = t - ret; + nl = l - old_len + new_len; + + if (!GREEDY_REALLOC(ret, allocated, nl + 1)) + return mfree(ret); + + l = nl; + t = ret + d; + + t = stpcpy(t, new_string); + f += old_len; + } + + *t = 0; + return ret; +} + +static void advance_offsets(ssize_t diff, size_t offsets[static 2], size_t shift[static 2], size_t size) { + if (!offsets) + return; + + if ((size_t) diff < offsets[0]) + shift[0] += size; + if ((size_t) diff < offsets[1]) + shift[1] += size; +} + +char *strip_tab_ansi(char **ibuf, size_t *_isz, size_t highlight[2]) { + const char *i, *begin = NULL; + enum { + STATE_OTHER, + STATE_ESCAPE, + STATE_CSI, + STATE_CSO, + } state = STATE_OTHER; + char *obuf = NULL; + size_t osz = 0, isz, shift[2] = {}; + FILE *f; + + assert(ibuf); + assert(*ibuf); + + /* This does three things: + * + * 1. Replaces TABs by 8 spaces + * 2. Strips ANSI color sequences (a subset of CSI), i.e. ESC '[' … 'm' sequences + * 3. Strips ANSI operating system sequences (CSO), i.e. ESC ']' … BEL sequences + * + * Everything else will be left as it is. In particular other ANSI sequences are left as they are, as are any + * other special characters. Truncated ANSI sequences are left-as is too. This call is supposed to suppress the + * most basic formatting noise, but nothing else. + * + * Why care for CSO sequences? Well, to undo what terminal_urlify() and friends generate. */ + + isz = _isz ? *_isz : strlen(*ibuf); + + f = open_memstream(&obuf, &osz); + if (!f) + return NULL; + + /* Note we turn off internal locking on f for performance reasons. It's safe to do so since we created f here + * and it doesn't leave our scope. */ + + (void) __fsetlocking(f, FSETLOCKING_BYCALLER); + + 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); + advance_offsets(i - *ibuf, highlight, shift, 7); + } else + fputc(*i, f); + + break; + + case STATE_ESCAPE: + if (i >= *ibuf + isz) { /* EOT */ + fputc('\x1B', f); + advance_offsets(i - *ibuf, highlight, shift, 1); + break; + } else if (*i == '[') { /* ANSI CSI */ + state = STATE_CSI; + begin = i + 1; + } else if (*i == ']') { /* ANSI CSO */ + state = STATE_CSO; + begin = i + 1; + } else { + fputc('\x1B', f); + fputc(*i, f); + advance_offsets(i - *ibuf, highlight, shift, 1); + state = STATE_OTHER; + } + + break; + + case STATE_CSI: + + if (i >= *ibuf + isz || /* EOT … */ + !strchr("01234567890;m", *i)) { /* … or invalid chars in sequence */ + fputc('\x1B', f); + fputc('[', f); + advance_offsets(i - *ibuf, highlight, shift, 2); + state = STATE_OTHER; + i = begin-1; + } else if (*i == 'm') + state = STATE_OTHER; + + break; + + case STATE_CSO: + + if (i >= *ibuf + isz || /* EOT … */ + (*i != '\a' && (uint8_t) *i < 32U) || (uint8_t) *i > 126U) { /* … or invalid chars in sequence */ + fputc('\x1B', f); + fputc(']', f); + advance_offsets(i - *ibuf, highlight, shift, 2); + state = STATE_OTHER; + i = begin-1; + } else if (*i == '\a') + state = STATE_OTHER; + + break; + } + } + + if (fflush_and_check(f) < 0) { + fclose(f); + return mfree(obuf); + } + + fclose(f); + + free(*ibuf); + *ibuf = obuf; + + if (_isz) + *_isz = osz; + + if (highlight) { + highlight[0] += shift[0]; + highlight[1] += shift[1]; + } + + return obuf; +} + +char *strextend_with_separator(char **x, const char *separator, ...) { + bool need_separator; + size_t f, l, l_separator; + char *r, *p; + va_list ap; + + assert(x); + + l = f = strlen_ptr(*x); + + need_separator = !isempty(*x); + l_separator = strlen_ptr(separator); + + va_start(ap, separator); + for (;;) { + const char *t; + size_t n; + + t = va_arg(ap, const char *); + if (!t) + break; + + n = strlen(t); + + if (need_separator) + n += l_separator; + + if (n > ((size_t) -1) - l) { + va_end(ap); + return NULL; + } + + l += n; + need_separator = true; + } + va_end(ap); + + need_separator = !isempty(*x); + + r = realloc(*x, l+1); + if (!r) + return NULL; + + p = r + f; + + va_start(ap, separator); + for (;;) { + const char *t; + + t = va_arg(ap, const char *); + if (!t) + break; + + if (need_separator && separator) + p = stpcpy(p, separator); + + p = stpcpy(p, t); + + need_separator = true; + } + va_end(ap); + + assert(p == r + l); + + *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 a 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; +} + +int free_and_strndup(char **p, const char *s, size_t l) { + char *t; + + assert(p); + assert(s || l == 0); + + /* Replaces a string pointer with a strndup()ed new string, + * freeing the old one. */ + + if (!*p && !s) + return 0; + + if (*p && s && strneq(*p, s, l) && (l > strlen(*p) || (*p)[l] == '\0')) + return 0; + + if (s) { + t = strndup(s, l); + if (!t) + return -ENOMEM; + } else + t = NULL; + + free_and_replace(*p, t); + return 1; +} + +#if !HAVE_EXPLICIT_BZERO +/* + * Pointer to memset is volatile so that compiler must de-reference + * the pointer and can't assume that it points to any function in + * particular (such as memset, which it then might further "optimize") + * This approach is inspired by openssl's crypto/mem_clr.c. + */ +typedef void *(*memset_t)(void *,int,size_t); + +static volatile memset_t memset_func = memset; + +void* explicit_bzero_safe(void *p, size_t l) { + if (l > 0) + memset_func(p, '\0', l); + + return p; +} +#endif + +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. */ + explicit_bzero_safe(x, strlen(x)); + return 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; +} |