freebsd-dev/lib/libutil/property.c
John Baldwin a54bb702d7 Restore the previous state after a FILL operation in properties_read()
rather than forcing the state to LOOK.  If we are in the middle of parsing
a line when we have to do a FILL we would have lost any token we were in
the middle of parsing and would have treated the next character as being
at the start of a new line instead.

PR:		kern/89181
Submitted by:	Antony Mawer gnats at mawer dot org
MFC after:	1 week
2005-11-28 16:30:16 +00:00

260 lines
5.8 KiB
C

/*
*
* Simple property list handling code.
*
* Copyright (c) 1998
* Jordan Hubbard. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer,
* verbatim and that no modifications are made prior to this
* point in the file.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR HIS PETS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, LIFE OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <ctype.h>
#include <err.h>
#include <libutil.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static properties
property_alloc(char *name, char *value)
{
properties n;
if ((n = (properties)malloc(sizeof(struct _property))) == NULL)
return (NULL);
n->next = NULL;
if (name != NULL) {
if ((n->name = strdup(name)) == NULL) {
free(n);
return (NULL);
}
} else
n->name = NULL;
if (value != NULL) {
if ((n->value = strdup(value)) == NULL) {
free(n->name);
free(n);
return (NULL);
}
} else
n->value = NULL;
return (n);
}
properties
properties_read(int fd)
{
properties head, ptr;
char hold_n[PROPERTY_MAX_NAME + 1];
char hold_v[PROPERTY_MAX_VALUE + 1];
char buf[BUFSIZ * 4];
int bp, n, v, max;
enum { LOOK, COMMENT, NAME, VALUE, MVALUE, COMMIT, FILL, STOP } state, last_state;
int ch = 0, blevel = 0;
n = v = bp = max = 0;
head = ptr = NULL;
state = last_state = LOOK;
while (state != STOP) {
if (state != COMMIT) {
if (bp == max) {
last_state = state;
state = FILL;
} else
ch = buf[bp++];
}
switch(state) {
case FILL:
if ((max = read(fd, buf, sizeof buf)) < 0) {
properties_free(head);
return (NULL);
}
if (max == 0) {
state = STOP;
} else {
/*
* Restore the state from before the fill (which will be
* initialised to LOOK for the first FILL). This ensures that
* if we were part-way through eg., a VALUE state, when the
* buffer ran out, that the previous operation will be allowed
* to complete.
*/
state = last_state;
ch = buf[0];
bp = 0;
}
continue;
case LOOK:
if (isspace((unsigned char)ch))
continue;
/* Allow shell or lisp style comments */
else if (ch == '#' || ch == ';') {
state = COMMENT;
continue;
}
else if (isalnum((unsigned char)ch) || ch == '_') {
if (n >= PROPERTY_MAX_NAME) {
n = 0;
state = COMMENT;
}
else {
hold_n[n++] = ch;
state = NAME;
}
}
else
state = COMMENT; /* Ignore the rest of the line */
break;
case COMMENT:
if (ch == '\n')
state = LOOK;
break;
case NAME:
if (ch == '\n' || !ch) {
hold_n[n] = '\0';
hold_v[0] = '\0';
v = n = 0;
state = COMMIT;
}
else if (isspace((unsigned char)ch))
continue;
else if (ch == '=') {
hold_n[n] = '\0';
v = n = 0;
state = VALUE;
}
else
hold_n[n++] = ch;
break;
case VALUE:
if (v == 0 && ch == '\n') {
hold_v[v] = '\0';
v = n = 0;
state = COMMIT;
}
else if (v == 0 && isspace((unsigned char)ch))
continue;
else if (ch == '{') {
state = MVALUE;
++blevel;
}
else if (ch == '\n' || !ch) {
hold_v[v] = '\0';
v = n = 0;
state = COMMIT;
}
else {
if (v >= PROPERTY_MAX_VALUE) {
state = COMMENT;
v = n = 0;
break;
}
else
hold_v[v++] = ch;
}
break;
case MVALUE:
/* multiline value */
if (v >= PROPERTY_MAX_VALUE) {
warn("properties_read: value exceeds max length");
state = COMMENT;
n = v = 0;
}
else if (ch == '}' && !--blevel) {
hold_v[v] = '\0';
v = n = 0;
state = COMMIT;
}
else {
hold_v[v++] = ch;
if (ch == '{')
++blevel;
}
break;
case COMMIT:
if (head == NULL) {
if ((head = ptr = property_alloc(hold_n, hold_v)) == NULL)
return (NULL);
} else {
if ((ptr->next = property_alloc(hold_n, hold_v)) == NULL) {
properties_free(head);
return (NULL);
}
ptr = ptr->next;
}
state = LOOK;
v = n = 0;
break;
case STOP:
/* we don't handle this here, but this prevents warnings */
break;
}
}
if (head == NULL && (head = property_alloc(NULL, NULL)) == NULL)
return (NULL);
return (head);
}
char *
property_find(properties list, const char *name)
{
if (list == NULL || name == NULL || !name[0])
return (NULL);
while (list != NULL) {
if (list->name != NULL && strcmp(list->name, name) == 0)
return (list->value);
list = list->next;
}
return (NULL);
}
void
properties_free(properties list)
{
properties tmp;
while (list) {
tmp = list->next;
if (list->name)
free(list->name);
if (list->value)
free(list->value);
free(list);
list = tmp;
}
}