rooty/LibrePilot
1
0
Fork 0
mirror of https://bitbucket.org/librepilot/librepilot.git synced 2025-01-18 03:52:11 +01:00
Code Issues Releases Activity

Made printf-stdarg check maximum string length limit (supports snprintf now)

Browse Source
This commit is contained in:
Corvus Corax 2013-11-17 02:47:58 +01:00
parent 314d526e94
commit 320bbcf434
1 changed files with 31 additions and 32 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

63
flight/libraries/printf-stdarg.c
View File

@ -54,9 +54,9 @@ static void printchar(char * *str, int c)
#define PAD_RIGHT 1 #define PAD_RIGHT 1
#define PAD_ZERO 2 #define PAD_ZERO 2
static int prints(char * *out, const char *string, int width, int pad) static int prints(char * *out, const char *string, int width, int pad, int limit)
{ {
register int pc = 0, padchar = ' '; register int pc = limit, padchar = ' ';
if (width > 0) { if (width > 0) {
register int len = 0; register int len = 0;
@ -74,37 +74,37 @@ static int prints(char * *out, const char *string, int width, int pad)
} }
} }
if (!(pad & PAD_RIGHT)) { if (!(pad & PAD_RIGHT)) {
for (; width > 0; --width) { for (; width > 0 && pc; --width) {
printchar(out, padchar); printchar(out, padchar);
++pc; --pc;
} }
} }
for (; *string; ++string) { for (; *string && pc; ++string) {
printchar(out, *string); printchar(out, *string);
++pc; --pc;
} }
for (; width > 0; --width) { for (; width > 0 && pc; --width) {
printchar(out, padchar); printchar(out, padchar);
++pc; --pc;
} }
return pc; return limit - pc;
} }
/* the following should be enough for 32 bit int */ /* the following should be enough for 32 bit int */
#define PRINT_BUF_LEN 12 #define PRINT_BUF_LEN 12
static int printi(char * *out, int i, int b, int sg, int width, int pad, int letbase) static int printi(char * *out, int i, int b, int sg, int width, int pad, int letbase, int limit)
{ {
char print_buf[PRINT_BUF_LEN]; char print_buf[PRINT_BUF_LEN];
register char *s; register char *s;
register int t, neg = 0, pc = 0; register int t, neg = 0, pc = limit;
register unsigned int u = i; register unsigned int u = i;
if (i == 0) { if (i == 0) {
print_buf[0] = '0'; print_buf[0] = '0';
print_buf[1] = '\0'; print_buf[1] = '\0';
return prints(out, print_buf, width, pad); return prints(out, print_buf, width, pad, limit);
} }
if (sg && b == 10 && i < 0) { if (sg && b == 10 && i < 0) {
@ -124,26 +124,26 @@ static int printi(char * *out, int i, int b, int sg, int width, int pad, int let
u /= b; u /= b;
} }
if (neg) { if (neg && pc) {
if (width && (pad & PAD_ZERO)) { if (width && (pad & PAD_ZERO)) {
printchar(out, '-'); printchar(out, '-');
++pc; --pc;
--width; --width;
} else { } else {
*--s = '-'; *--s = '-';
} }
} }
return pc + prints(out, s, width, pad); return (limit - pc) + prints(out, s, width, pad, pc);
} }
static int print(char * *out, const char *format, va_list args) static int print(int limit, char * *out, const char *format, va_list args)
{ {
register int width, pad; register int width, pad;
register int pc = 0; register int pc = limit;
char scr[2]; char scr[2];
for (; *format != 0; ++format) { for (; *format != 0 && pc; ++format) {
if (*format == '%') { if (*format == '%') {
++format; ++format;
width = pad = 0; width = pad = 0;
@ -167,43 +167,43 @@ static int print(char * *out, const char *format, va_list args)
} }
if (*format == 's') { if (*format == 's') {
register char *s = (char *)va_arg(args, int); register char *s = (char *)va_arg(args, int);
pc += prints(out, s ? s : "(null)", width, pad); pc -= prints(out, s ? s : "(null)", width, pad, pc);
continue; continue;
} }
if (*format == 'd') { if (*format == 'd') {
pc += printi(out, va_arg(args, int), 10, 1, width, pad, 'a'); pc -= printi(out, va_arg(args, int), 10, 1, width, pad, 'a', pc);
continue; continue;
} }
if (*format == 'x') { if (*format == 'x') {
pc += printi(out, va_arg(args, int), 16, 0, width, pad, 'a'); pc -= printi(out, va_arg(args, int), 16, 0, width, pad, 'a', pc);
continue; continue;
} }
if (*format == 'X') { if (*format == 'X') {
pc += printi(out, va_arg(args, int), 16, 0, width, pad, 'A'); pc -= printi(out, va_arg(args, int), 16, 0, width, pad, 'A', pc);
continue; continue;
} }
if (*format == 'u') { if (*format == 'u') {
pc += printi(out, va_arg(args, int), 10, 0, width, pad, 'a'); pc -= printi(out, va_arg(args, int), 10, 0, width, pad, 'a', pc);
continue; continue;
} }
if (*format == 'c') { if (*format == 'c') {
/* char are converted to int then pushed on the stack */ /* char are converted to int then pushed on the stack */
scr[0] = (char)va_arg(args, int); scr[0] = (char)va_arg(args, int);
scr[1] = '\0'; scr[1] = '\0';
pc += prints(out, scr, width, pad); pc -= prints(out, scr, width, pad, pc);
continue; continue;
} }
} else { } else {
out: out:
printchar(out, *format); printchar(out, *format);
++pc; --pc;
} }
} }
if (out) { if (out) {
**out = '\0'; **out = '\0';
} }
va_end(args); va_end(args);
return pc; return limit - pc;
} }
int printf(const char *format, ...) int printf(const char *format, ...)
@ -211,13 +211,13 @@ int printf(const char *format, ...)
va_list args; va_list args;
va_start(args, format); va_start(args, format);
return print(0, format, args); return print(-1, 0, format, args);
} }
// TK: added for alternative parameter passing // TK: added for alternative parameter passing
int vprintf(const char *format, va_list args) int vprintf(const char *format, va_list args)
{ {
return print(0, format, args); return print(-1, 0, format, args);
} }
int sprintf(char *out, const char *format, ...) int sprintf(char *out, const char *format, ...)
@ -225,7 +225,7 @@ int sprintf(char *out, const char *format, ...)
va_list args; va_list args;
va_start(args, format); va_start(args, format);
return print(&out, format, args); return print(-1, &out, format, args);
} }
// TK: added for alternative parameter passing // TK: added for alternative parameter passing
@ -234,17 +234,16 @@ int vsprintf(char *out, const char *format, va_list args)
char *_out; char *_out;
_out = out; _out = out;
return print(&_out, format, args); return print(-1, &_out, format, args);
} }
int snprintf(char *buf, size_t count, const char *format, ...) int snprintf(char *buf, size_t count, const char *format, ...)
{ {
va_list args; va_list args;
(void)count;
va_start(args, format); va_start(args, format);
return print(&buf, format, args); return print(count, &buf, format, args);
} }
/** /**