Adding upstream version 247.3.upstream/247.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 549 insertions, 0 deletions

diff --git a/src/basic/escape.c b/src/basic/escape.c
new file mode 100644
index 0000000..31f3cda
--- /dev/null
+++ b/src/basic/escape.c
@@ -0,0 +1,549 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "alloc-util.h"
+#include "escape.h"
+#include "hexdecoct.h"
+#include "macro.h"
+#include "utf8.h"
+
+int cescape_char(char c, char *buf) {
+        char *buf_old = buf;
+
+        /* Needs space for 4 characters in the buffer */
+
+        switch (c) {
+
+                case '\a':
+                        *(buf++) = '\\';
+                        *(buf++) = 'a';
+                        break;
+                case '\b':
+                        *(buf++) = '\\';
+                        *(buf++) = 'b';
+                        break;
+                case '\f':
+                        *(buf++) = '\\';
+                        *(buf++) = 'f';
+                        break;
+                case '\n':
+                        *(buf++) = '\\';
+                        *(buf++) = 'n';
+                        break;
+                case '\r':
+                        *(buf++) = '\\';
+                        *(buf++) = 'r';
+                        break;
+                case '\t':
+                        *(buf++) = '\\';
+                        *(buf++) = 't';
+                        break;
+                case '\v':
+                        *(buf++) = '\\';
+                        *(buf++) = 'v';
+                        break;
+                case '\\':
+                        *(buf++) = '\\';
+                        *(buf++) = '\\';
+                        break;
+                case '"':
+                        *(buf++) = '\\';
+                        *(buf++) = '"';
+                        break;
+                case '\'':
+                        *(buf++) = '\\';
+                        *(buf++) = '\'';
+                        break;
+
+                default:
+                        /* For special chars we prefer octal over
+                         * hexadecimal encoding, simply because glib's
+                         * g_strescape() does the same */
+                        if ((c < ' ') || (c >= 127)) {
+                                *(buf++) = '\\';
+                                *(buf++) = octchar((unsigned char) c >> 6);
+                                *(buf++) = octchar((unsigned char) c >> 3);
+                                *(buf++) = octchar((unsigned char) c);
+                        } else
+                                *(buf++) = c;
+                        break;
+        }
+
+        return buf - buf_old;
+}
+
+char* cescape_length(const char *s, size_t n) {
+        const char *f;
+        char *r, *t;
+
+        assert(s || n == 0);
+
+        /* Does C style string escaping. May be reversed with
+         * cunescape(). */
+
+        r = new(char, n*4 + 1);
+        if (!r)
+                return NULL;
+
+        for (f = s, t = r; f < s + n; f++)
+                t += cescape_char(*f, t);
+
+        *t = 0;
+
+        return r;
+}
+
+char* cescape(const char *s) {
+        assert(s);
+
+        return cescape_length(s, strlen(s));
+}
+
+int cunescape_one(const char *p, size_t length, char32_t *ret, bool *eight_bit, bool accept_nul) {
+        int r = 1;
+
+        assert(p);
+        assert(ret);
+
+        /* Unescapes C style. Returns the unescaped character in ret.
+         * Sets *eight_bit to true if the escaped sequence either fits in
+         * one byte in UTF-8 or is a non-unicode literal byte and should
+         * instead be copied directly.
+         */
+
+        if (length != (size_t) -1 && length < 1)
+                return -EINVAL;
+
+        switch (p[0]) {
+
+        case 'a':
+                *ret = '\a';
+                break;
+        case 'b':
+                *ret = '\b';
+                break;
+        case 'f':
+                *ret = '\f';
+                break;
+        case 'n':
+                *ret = '\n';
+                break;
+        case 'r':
+                *ret = '\r';
+                break;
+        case 't':
+                *ret = '\t';
+                break;
+        case 'v':
+                *ret = '\v';
+                break;
+        case '\\':
+                *ret = '\\';
+                break;
+        case '"':
+                *ret = '"';
+                break;
+        case '\'':
+                *ret = '\'';
+                break;
+
+        case 's':
+                /* This is an extension of the XDG syntax files */
+                *ret = ' ';
+                break;
+
+        case 'x': {
+                /* hexadecimal encoding */
+                int a, b;
+
+                if (length != (size_t) -1 && length < 3)
+                        return -EINVAL;
+
+                a = unhexchar(p[1]);
+                if (a < 0)
+                        return -EINVAL;
+
+                b = unhexchar(p[2]);
+                if (b < 0)
+                        return -EINVAL;
+
+                /* Don't allow NUL bytes */
+                if (a == 0 && b == 0 && !accept_nul)
+                        return -EINVAL;
+
+                *ret = (a << 4U) | b;
+                *eight_bit = true;
+                r = 3;
+                break;
+        }
+
+        case 'u': {
+                /* C++11 style 16bit unicode */
+
+                int a[4];
+                size_t i;
+                uint32_t c;
+
+                if (length != (size_t) -1 && length < 5)
+                        return -EINVAL;
+
+                for (i = 0; i < 4; i++) {
+                        a[i] = unhexchar(p[1 + i]);
+                        if (a[i] < 0)
+                                return a[i];
+                }
+
+                c = ((uint32_t) a[0] << 12U) | ((uint32_t) a[1] << 8U) | ((uint32_t) a[2] << 4U) | (uint32_t) a[3];
+
+                /* Don't allow 0 chars */
+                if (c == 0 && !accept_nul)
+                        return -EINVAL;
+
+                *ret = c;
+                r = 5;
+                break;
+        }
+
+        case 'U': {
+                /* C++11 style 32bit unicode */
+
+                int a[8];
+                size_t i;
+                char32_t c;
+
+                if (length != (size_t) -1 && length < 9)
+                        return -EINVAL;
+
+                for (i = 0; i < 8; i++) {
+                        a[i] = unhexchar(p[1 + i]);
+                        if (a[i] < 0)
+                                return a[i];
+                }
+
+                c = ((uint32_t) a[0] << 28U) | ((uint32_t) a[1] << 24U) | ((uint32_t) a[2] << 20U) | ((uint32_t) a[3] << 16U) |
+                    ((uint32_t) a[4] << 12U) | ((uint32_t) a[5] <<  8U) | ((uint32_t) a[6] <<  4U) |  (uint32_t) a[7];
+
+                /* Don't allow 0 chars */
+                if (c == 0 && !accept_nul)
+                        return -EINVAL;
+
+                /* Don't allow invalid code points */
+                if (!unichar_is_valid(c))
+                        return -EINVAL;
+
+                *ret = c;
+                r = 9;
+                break;
+        }
+
+        case '0':
+        case '1':
+        case '2':
+        case '3':
+        case '4':
+        case '5':
+        case '6':
+        case '7': {
+                /* octal encoding */
+                int a, b, c;
+                char32_t m;
+
+                if (length != (size_t) -1 && length < 3)
+                        return -EINVAL;
+
+                a = unoctchar(p[0]);
+                if (a < 0)
+                        return -EINVAL;
+
+                b = unoctchar(p[1]);
+                if (b < 0)
+                        return -EINVAL;
+
+                c = unoctchar(p[2]);
+                if (c < 0)
+                        return -EINVAL;
+
+                /* don't allow NUL bytes */
+                if (a == 0 && b == 0 && c == 0 && !accept_nul)
+                        return -EINVAL;
+
+                /* Don't allow bytes above 255 */
+                m = ((uint32_t) a << 6U) | ((uint32_t) b << 3U) | (uint32_t) c;
+                if (m > 255)
+                        return -EINVAL;
+
+                *ret = m;
+                *eight_bit = true;
+                r = 3;
+                break;
+        }
+
+        default:
+                return -EINVAL;
+        }
+
+        return r;
+}
+
+int cunescape_length_with_prefix(const char *s, size_t length, const char *prefix, UnescapeFlags flags, char **ret) {
+        char *r, *t;
+        const char *f;
+        size_t pl;
+
+        assert(s);
+        assert(ret);
+
+        /* Undoes C style string escaping, and optionally prefixes it. */
+
+        pl = strlen_ptr(prefix);
+
+        r = new(char, pl+length+1);
+        if (!r)
+                return -ENOMEM;
+
+        if (prefix)
+                memcpy(r, prefix, pl);
+
+        for (f = s, t = r + pl; f < s + length; f++) {
+                size_t remaining;
+                bool eight_bit = false;
+                char32_t u;
+                int k;
+
+                remaining = s + length - f;
+                assert(remaining > 0);
+
+                if (*f != '\\') {
+                        /* A literal, copy verbatim */
+                        *(t++) = *f;
+                        continue;
+                }
+
+                if (remaining == 1) {
+                        if (flags & UNESCAPE_RELAX) {
+                                /* A trailing backslash, copy verbatim */
+                                *(t++) = *f;
+                                continue;
+                        }
+
+                        free(r);
+                        return -EINVAL;
+                }
+
+                k = cunescape_one(f + 1, remaining - 1, &u, &eight_bit, flags & UNESCAPE_ACCEPT_NUL);
+                if (k < 0) {
+                        if (flags & UNESCAPE_RELAX) {
+                                /* Invalid escape code, let's take it literal then */
+                                *(t++) = '\\';
+                                continue;
+                        }
+
+                        free(r);
+                        return k;
+                }
+
+                f += k;
+                if (eight_bit)
+                        /* One byte? Set directly as specified */
+                        *(t++) = u;
+                else
+                        /* Otherwise encode as multi-byte UTF-8 */
+                        t += utf8_encode_unichar(t, u);
+        }
+
+        *t = 0;
+
+        *ret = r;
+        return t - r;
+}
+
+char* xescape_full(const char *s, const char *bad, size_t console_width, bool eight_bits) {
+        char *ans, *t, *prev, *prev2;
+        const char *f;
+
+        /* Escapes all chars in bad, in addition to \ and all special chars, in \xFF style escaping. May be
+         * reversed with cunescape(). If eight_bits is true, characters >= 127 are let through unchanged.
+         * This corresponds to non-ASCII printable characters in pre-unicode encodings.
+         *
+         * If console_width is reached, output is truncated and "..." is appended. */
+
+        if (console_width == 0)
+                return strdup("");
+
+        ans = new(char, MIN(strlen(s), console_width) * 4 + 1);
+        if (!ans)
+                return NULL;
+
+        memset(ans, '_', MIN(strlen(s), console_width) * 4);
+        ans[MIN(strlen(s), console_width) * 4] = 0;
+
+        for (f = s, t = prev = prev2 = ans; ; f++) {
+                char *tmp_t = t;
+
+                if (!*f) {
+                        *t = 0;
+                        return ans;
+                }
+
+                if ((unsigned char) *f < ' ' || (!eight_bits && (unsigned char) *f >= 127) ||
+                    *f == '\\' || strchr(bad, *f)) {
+                        if ((size_t) (t - ans) + 4 > console_width)
+                                break;
+
+                        *(t++) = '\\';
+                        *(t++) = 'x';
+                        *(t++) = hexchar(*f >> 4);
+                        *(t++) = hexchar(*f);
+                } else {
+                        if ((size_t) (t - ans) + 1 > console_width)
+                                break;
+
+                        *(t++) = *f;
+                }
+
+                /* We might need to go back two cycles to fit three dots, so remember two positions */
+                prev2 = prev;
+                prev = tmp_t;
+        }
+
+        /* We can just write where we want, since chars are one-byte */
+        size_t c = MIN(console_width, 3u); /* If the console is too narrow, write fewer dots */
+        size_t off;
+        if (console_width - c >= (size_t) (t - ans))
+                off = (size_t) (t - ans);
+        else if (console_width - c >= (size_t) (prev - ans))
+                off = (size_t) (prev - ans);
+        else if (console_width - c >= (size_t) (prev2 - ans))
+                off = (size_t) (prev2 - ans);
+        else
+                off = console_width - c;
+        assert(off <= (size_t) (t - ans));
+
+        memcpy(ans + off, "...", c);
+        ans[off + c] = '\0';
+        return ans;
+}
+
+char* escape_non_printable_full(const char *str, size_t console_width, bool eight_bit) {
+        if (eight_bit)
+                return xescape_full(str, "", console_width, true);
+        else
+                return utf8_escape_non_printable_full(str, console_width);
+}
+
+char* octescape(const char *s, size_t len) {
+        char *r, *t;
+        const char *f;
+
+        /* Escapes all chars in bad, in addition to \ and " chars,
+         * in \nnn style escaping. */
+
+        r = new(char, len * 4 + 1);
+        if (!r)
+                return NULL;
+
+        for (f = s, t = r; f < s + len; f++) {
+
+                if (*f < ' ' || *f >= 127 || IN_SET(*f, '\\', '"')) {
+                        *(t++) = '\\';
+                        *(t++) = '0' + (*f >> 6);
+                        *(t++) = '0' + ((*f >> 3) & 8);
+                        *(t++) = '0' + (*f & 8);
+                } else
+                        *(t++) = *f;
+        }
+
+        *t = 0;
+
+        return r;
+
+}
+
+static char* strcpy_backslash_escaped(char *t, const char *s, const char *bad, bool escape_tab_nl) {
+        assert(bad);
+
+        for (; *s; s++) {
+                if (escape_tab_nl && IN_SET(*s, '\n', '\t')) {
+                        *(t++) = '\\';
+                        *(t++) = *s == '\n' ? 'n' : 't';
+                        continue;
+                }
+
+                if (*s == '\\' || strchr(bad, *s))
+                        *(t++) = '\\';
+
+                *(t++) = *s;
+        }
+
+        return t;
+}
+
+char* shell_escape(const char *s, const char *bad) {
+        char *r, *t;
+
+        r = new(char, strlen(s)*2+1);
+        if (!r)
+                return NULL;
+
+        t = strcpy_backslash_escaped(r, s, bad, false);
+        *t = 0;
+
+        return r;
+}
+
+char* shell_maybe_quote(const char *s, EscapeStyle style) {
+        const char *p;
+        char *r, *t;
+
+        assert(s);
+
+        /* Encloses a string in quotes if necessary to make it OK as a shell
+         * string. Note that we treat benign UTF-8 characters as needing
+         * escaping too, but that should be OK. */
+
+        for (p = s; *p; p++)
+                if (*p <= ' ' ||
+                    *p >= 127 ||
+                    strchr(SHELL_NEED_QUOTES, *p))
+                        break;
+
+        if (!*p)
+                return strdup(s);
+
+        r = new(char, (style == ESCAPE_POSIX) + 1 + strlen(s)*2 + 1 + 1);
+        if (!r)
+                return NULL;
+
+        t = r;
+        switch (style) {
+        case ESCAPE_BACKSLASH:
+        case ESCAPE_BACKSLASH_ONELINE:
+                *(t++) = '"';
+                break;
+        case ESCAPE_POSIX:
+                *(t++) = '$';
+                *(t++) = '\'';
+                break;
+        default:
+                assert_not_reached("Bad EscapeStyle");
+        }
+
+        t = mempcpy(t, s, p - s);
+
+        if (IN_SET(style, ESCAPE_BACKSLASH, ESCAPE_BACKSLASH_ONELINE))
+                t = strcpy_backslash_escaped(t, p, SHELL_NEED_ESCAPE,
+                                             style == ESCAPE_BACKSLASH_ONELINE);
+        else
+                t = strcpy_backslash_escaped(t, p, SHELL_NEED_ESCAPE_POSIX, true);
+
+        if (IN_SET(style, ESCAPE_BACKSLASH, ESCAPE_BACKSLASH_ONELINE))
+                *(t++) = '"';
+        else
+                *(t++) = '\'';
+        *t = 0;
+
+        return r;
+}