diff options
Diffstat (limited to 'src/libbasic/xml.c')
| -rw-r--r-- | src/libbasic/xml.c | 255 |
1 files changed, 255 insertions, 0 deletions
diff --git a/src/libbasic/xml.c b/src/libbasic/xml.c new file mode 100644 index 0000000000..1dbeac7324 --- /dev/null +++ b/src/libbasic/xml.c @@ -0,0 +1,255 @@ +/*** + This file is part of systemd. + + Copyright 2013 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 <stddef.h> +#include <string.h> + +#include "macro.h" +#include "string-util.h" +#include "xml.h" + +enum { + STATE_NULL, + STATE_TEXT, + STATE_TAG, + STATE_ATTRIBUTE, +}; + +static void inc_lines(unsigned *line, const char *s, size_t n) { + const char *p = s; + + if (!line) + return; + + for (;;) { + const char *f; + + f = memchr(p, '\n', n); + if (!f) + return; + + n -= (f - p) + 1; + p = f + 1; + (*line)++; + } +} + +/* We don't actually do real XML here. We only read a simplistic + * subset, that is a bit less strict that XML and lacks all the more + * complex features, like entities, or namespaces. However, we do + * support some HTML5-like simplifications */ + +int xml_tokenize(const char **p, char **name, void **state, unsigned *line) { + const char *c, *e, *b; + char *ret; + int t; + + assert(p); + assert(*p); + assert(name); + assert(state); + + t = PTR_TO_INT(*state); + c = *p; + + if (t == STATE_NULL) { + if (line) + *line = 1; + t = STATE_TEXT; + } + + for (;;) { + if (*c == 0) + return XML_END; + + switch (t) { + + case STATE_TEXT: { + int x; + + e = strchrnul(c, '<'); + if (e > c) { + /* More text... */ + ret = strndup(c, e - c); + if (!ret) + return -ENOMEM; + + inc_lines(line, c, e - c); + + *name = ret; + *p = e; + *state = INT_TO_PTR(STATE_TEXT); + + return XML_TEXT; + } + + assert(*e == '<'); + b = c + 1; + + if (startswith(b, "!--")) { + /* A comment */ + e = strstr(b + 3, "-->"); + if (!e) + return -EINVAL; + + inc_lines(line, b, e + 3 - b); + + c = e + 3; + continue; + } + + if (*b == '?') { + /* Processing instruction */ + + e = strstr(b + 1, "?>"); + if (!e) + return -EINVAL; + + inc_lines(line, b, e + 2 - b); + + c = e + 2; + continue; + } + + if (*b == '!') { + /* DTD */ + + e = strchr(b + 1, '>'); + if (!e) + return -EINVAL; + + inc_lines(line, b, e + 1 - b); + + c = e + 1; + continue; + } + + if (*b == '/') { + /* A closing tag */ + x = XML_TAG_CLOSE; + b++; + } else + x = XML_TAG_OPEN; + + e = strpbrk(b, WHITESPACE "/>"); + if (!e) + return -EINVAL; + + ret = strndup(b, e - b); + if (!ret) + return -ENOMEM; + + *name = ret; + *p = e; + *state = INT_TO_PTR(STATE_TAG); + + return x; + } + + case STATE_TAG: + + b = c + strspn(c, WHITESPACE); + if (*b == 0) + return -EINVAL; + + inc_lines(line, c, b - c); + + e = b + strcspn(b, WHITESPACE "=/>"); + if (e > b) { + /* An attribute */ + + ret = strndup(b, e - b); + if (!ret) + return -ENOMEM; + + *name = ret; + *p = e; + *state = INT_TO_PTR(STATE_ATTRIBUTE); + + return XML_ATTRIBUTE_NAME; + } + + if (startswith(b, "/>")) { + /* An empty tag */ + + *name = NULL; /* For empty tags we return a NULL name, the caller must be prepared for that */ + *p = b + 2; + *state = INT_TO_PTR(STATE_TEXT); + + return XML_TAG_CLOSE_EMPTY; + } + + if (*b != '>') + return -EINVAL; + + c = b + 1; + t = STATE_TEXT; + continue; + + case STATE_ATTRIBUTE: + + if (*c == '=') { + c++; + + if (*c == '\'' || *c == '\"') { + /* Tag with a quoted value */ + + e = strchr(c+1, *c); + if (!e) + return -EINVAL; + + inc_lines(line, c, e - c); + + ret = strndup(c+1, e - c - 1); + if (!ret) + return -ENOMEM; + + *name = ret; + *p = e + 1; + *state = INT_TO_PTR(STATE_TAG); + + return XML_ATTRIBUTE_VALUE; + + } + + /* Tag with a value without quotes */ + + b = strpbrk(c, WHITESPACE ">"); + if (!b) + b = c; + + ret = strndup(c, b - c); + if (!ret) + return -ENOMEM; + + *name = ret; + *p = b; + *state = INT_TO_PTR(STATE_TAG); + return XML_ATTRIBUTE_VALUE; + } + + t = STATE_TAG; + continue; + } + + } + + assert_not_reached("Bad state"); +} |