diff options
Diffstat (limited to 'util.c')
-rw-r--r-- | util.c | 99 |
1 files changed, 99 insertions, 0 deletions
@@ -25,6 +25,7 @@ #include <stdlib.h> #include <stdarg.h> #include <string.h> +#include <assert.h> #include "util.h" @@ -85,3 +86,101 @@ int util_is_printable_string(const void *data, int len) return 1; } + +/* + * Parse a octal encoded character starting at index i in string s. The + * resulting character will be returned and the index i will be updated to + * point at the character directly after the end of the encoding, this may be + * the '\0' terminator of the string. + */ +static char get_oct_char(const char *s, int *i) +{ + char x[4]; + char *endx; + long val; + + x[3] = '\0'; + strncpy(x, s + *i, 3); + + val = strtol(x, &endx, 8); + + assert(endx > x); + + (*i) += endx - x; + return val; +} + +/* + * Parse a hexadecimal encoded character starting at index i in string s. The + * resulting character will be returned and the index i will be updated to + * point at the character directly after the end of the encoding, this may be + * the '\0' terminator of the string. + */ +static char get_hex_char(const char *s, int *i) +{ + char x[3]; + char *endx; + long val; + + x[2] = '\0'; + strncpy(x, s + *i, 2); + + val = strtol(x, &endx, 16); + if (!(endx > x)) + die("\\x used with no following hex digits\n"); + + (*i) += endx - x; + return val; +} + +char get_escape_char(const char *s, int *i) +{ + char c = s[*i]; + int j = *i + 1; + char val; + + assert(c); + switch (c) { + case 'a': + val = '\a'; + break; + case 'b': + val = '\b'; + break; + case 't': + val = '\t'; + break; + case 'n': + val = '\n'; + break; + case 'v': + val = '\v'; + break; + case 'f': + val = '\f'; + break; + case 'r': + val = '\r'; + break; + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + j--; /* need to re-read the first digit as + * part of the octal value */ + val = get_oct_char(s, &j); + break; + case 'x': + val = get_hex_char(s, &j); + break; + default: + val = c; + } + + (*i) = j; + return val; +} |