diff options
Diffstat (limited to 'src/deh_str.c')
-rw-r--r-- | src/deh_str.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/src/deh_str.c b/src/deh_str.c index 0baaa7e8..9bd429b6 100644 --- a/src/deh_str.c +++ b/src/deh_str.c @@ -27,6 +27,7 @@ #include <stdio.h> #include <stdlib.h> #include <string.h> +#include <stdarg.h> #include "doomtype.h" #include "deh_str.h" @@ -179,3 +180,229 @@ void DEH_AddStringReplacement(char *from_text, char *to_text) DEH_AddToHashtable(sub); } +typedef enum +{ + FORMAT_ARG_INVALID, + FORMAT_ARG_INT, + FORMAT_ARG_FLOAT, + FORMAT_ARG_CHAR, + FORMAT_ARG_STRING, + FORMAT_ARG_PTR, + FORMAT_ARG_SAVE_POS +} format_arg_t; + +// Get the type of a format argument. +// We can mix-and-match different format arguments as long as they +// are for the same data type. + +static format_arg_t FormatArgumentType(char c) +{ + switch (c) + { + case 'd': case 'i': case 'o': case 'u': case 'x': case 'X': + return FORMAT_ARG_INT; + + case 'e': case 'E': case 'f': case 'F': case 'g': case 'G': + case 'a': case 'A': + return FORMAT_ARG_FLOAT; + + case 'c': case 'C': + return FORMAT_ARG_CHAR; + + case 's': case 'S': + return FORMAT_ARG_STRING; + + case 'p': + return FORMAT_ARG_PTR; + + case 'n': + return FORMAT_ARG_SAVE_POS; + + default: + return FORMAT_ARG_INVALID; + } +} + +// Given the specified string, get the type of the first format +// string encountered. + +static format_arg_t NextFormatArgument(char **str) +{ + format_arg_t argtype; + + // Search for the '%' starting the next string. + + while (**str != '\0') + { + if (**str == '%') + { + ++*str; + + // Don't stop for double-%s. + + if (**str != '%') + { + break; + } + } + + ++*str; + } + + // Find the type of the format string. + + while (**str != '\0') + { + argtype = FormatArgumentType(**str); + + if (argtype != FORMAT_ARG_INVALID) + { + ++*str; + + return argtype; + } + + ++*str; + } + + // Stop searching, we have reached the end. + + *str = NULL; + + return FORMAT_ARG_INVALID; +} + +// Check if the specified argument type is a valid replacement for +// the original. + +static boolean ValidArgumentReplacement(format_arg_t original, + format_arg_t replacement) +{ + // In general, the original and replacement types should be + // identical. However, there are some cases where the replacement + // is valid and the types don't match. + + // Characters can be represented as ints. + + if (original == FORMAT_ARG_CHAR && replacement == FORMAT_ARG_INT) + { + return true; + } + + // Strings are pointers. + + if (original == FORMAT_ARG_STRING && replacement == FORMAT_ARG_PTR) + { + return true; + } + + return original == replacement; +} + +// Return true if the specified string contains no format arguments. + +static boolean ValidFormatReplacement(char *original, char *replacement) +{ + char *rover1; + char *rover2; + int argtype1, argtype2; + + // Check each argument in turn and compare types. + + rover1 = original; rover2 = replacement; + + for (;;) + { + argtype1 = NextFormatArgument(&rover1); + argtype2 = NextFormatArgument(&rover2); + + if (argtype2 == FORMAT_ARG_INVALID) + { + // No more arguments left to read from the replacement string. + + break; + } + else if (argtype1 == FORMAT_ARG_INVALID) + { + // Replacement string has more arguments than the original. + + return false; + } + else if (!ValidArgumentReplacement(argtype1, argtype2)) + { + // Not a valid replacement argument. + + return false; + } + } + + return true; +} + +// Get replacement format string, checking arguments. + +static char *FormatStringReplacement(char *s) +{ + char *repl; + + repl = DEH_String(s); + + if (!ValidFormatReplacement(s, repl)) + { + printf("WARNING: Unsafe dehacked replacement provided for " + "printf format string: %s\n", s); + + return s; + } + + return repl; +} + +// printf(), performing a replacement on the format string. + +void DEH_printf(char *fmt, ...) +{ + va_list args; + char *repl; + + repl = FormatStringReplacement(fmt); + + va_start(args, fmt); + + vprintf(repl, args); + + va_end(args); +} + +// fprintf(), performing a replacement on the format string. + +void DEH_fprintf(FILE *fstream, char *fmt, ...) +{ + va_list args; + char *repl; + + repl = FormatStringReplacement(fmt); + + va_start(args, fmt); + + vfprintf(fstream, repl, args); + + va_end(args); +} + +// snprintf(), performing a replacement on the format string. + +void DEH_snprintf(char *buffer, size_t len, char *fmt, ...) +{ + va_list args; + char *repl; + + repl = FormatStringReplacement(fmt); + + va_start(args, fmt); + + vsnprintf(buffer, len, repl, args); + + va_end(args); +} + |