busybox/libbb/read_package_field.c

102 lines
2.4 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) many different people.
* If you wrote this, please acknowledge your work.
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include <stdlib.h>
#include <string.h>
#include "libbb.h"
/*
* Gets the next package field from package_buffer, seperated into the field name
* and field value, it returns the int offset to the first character of the next field
*/
int read_package_field(const char *package_buffer, char **field_name, char **field_value)
{
int offset_name_start = 0;
int offset_name_end = 0;
int offset_value_start = 0;
int offset_value_end = 0;
int offset = 0;
int next_offset;
int name_length;
int value_length;
int exit_flag = FALSE;
if (package_buffer == NULL) {
*field_name = NULL;
*field_value = NULL;
return(-1);
}
while (1) {
next_offset = offset + 1;
switch (package_buffer[offset]) {
case('\0'):
exit_flag = TRUE;
break;
case(':'):
if (offset_name_end == 0) {
offset_name_end = offset;
offset_value_start = next_offset;
}
/* TODO: Name might still have trailing spaces if ':' isnt
* immediately after name */
break;
case('\n'):
/* TODO: The char next_offset may be out of bounds */
if (package_buffer[next_offset] != ' ') {
exit_flag = TRUE;
break;
}
case('\t'):
case(' '):
/* increment the value start point if its a just filler */
if (offset_name_start == offset) {
offset_name_start++;
}
if (offset_value_start == offset) {
offset_value_start++;
}
break;
}
if (exit_flag) {
/* Check that the names are valid */
offset_value_end = offset;
name_length = offset_name_end - offset_name_start;
value_length = offset_value_end - offset_value_start;
if (name_length == 0) {
break;
}
if ((name_length > 0) && (value_length > 0)) {
break;
}
/* If not valid, start fresh with next field */
exit_flag = FALSE;
offset_name_start = offset + 1;
offset_name_end = 0;
offset_value_start = offset + 1;
offset_value_end = offset + 1;
offset++;
}
offset++;
}
if (name_length == 0) {
*field_name = NULL;
} else {
*field_name = bb_xstrndup(&package_buffer[offset_name_start], name_length);
}
if (value_length > 0) {
*field_value = bb_xstrndup(&package_buffer[offset_value_start], value_length);
} else {
*field_value = NULL;
}
return(next_offset);
}