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author | Andreas Baumann <mail@andreasbaumann.cc> | 2017-07-23 15:28:13 +0200 |
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committer | Andreas Baumann <mail@andreasbaumann.cc> | 2017-07-23 15:28:13 +0200 |
commit | ec9ed8deb79a9fd508a11b122453bb39d3b587a9 (patch) | |
tree | 6e35f78af8922083ff5b77dac04e4330e4ac0bb3 /src/libc | |
parent | ab8803f7cfdc7c7b258fb3e59fb2d55bacf7522a (diff) | |
download | abaos-ec9ed8deb79a9fd508a11b122453bb39d3b587a9.tar.gz abaos-ec9ed8deb79a9fd508a11b122453bb39d3b587a9.tar.bz2 |
added snprintf and a test for it
Diffstat (limited to 'src/libc')
-rw-r--r-- | src/libc/stdio.c | 101 | ||||
-rw-r--r-- | src/libc/stdio.h | 2 |
2 files changed, 103 insertions, 0 deletions
diff --git a/src/libc/stdio.c b/src/libc/stdio.c index 9fdf510..e0b87a8 100644 --- a/src/libc/stdio.c +++ b/src/libc/stdio.c @@ -150,6 +150,107 @@ int vprintf( const char *format, va_list args ) return n; } +int snprintf( char *buf, size_t n, const char *format, ... ) +{ + va_list args; + + va_start( args, format ); + int res = vsnprintf( buf, n, format, args ); + va_end( args ); + + return res; +} + +#define EMIT( x ) if( len < n ) { *buf = ( x ); buf++; *buf = '\0'; len++; } + +#define APPEND_STRING( s, s2 ) \ + strlcat( s, s2, n - len ); \ + s += strlen( s2 ); \ + len += strlen( s2 ); \ + if( len < n ) { \ + *s = '\0'; \ + } + +int vsnprintf( char *buf, size_t n, const char *format, va_list args ) +{ + const char *s = format; + int len = 0; + + *buf = '\0'; + while( *s != '\0' && len < n ) { + switch( *s ) { + case '\n': + EMIT( '\n' ); + break; + + case '%': + s++; + if( *s == '\0' ) { + strlcpy( buf, "<truncated % found at end of format string>", n - len ); + strlcat( buf, "\n", n - len - 1 ); + return -1; + } + + switch( *s ) { + case '%': + EMIT( '%' ); + break; + + case 'X': { + char buf2[19]; + itoa( va_arg( args, int ), (char *)buf2, 16 ); + APPEND_STRING( buf, buf2 ); + } + break; + + case 'd': { + char buf2[19]; + itoa( va_arg( args, int ), (char *)buf2, 10 ); + APPEND_STRING( buf, buf2 ); + } + break; + + case 'c': { + char buf2[2]; + buf2[0] = (char)va_arg( args, int ); + buf2[1] = '\0'; + APPEND_STRING( buf, buf2 ); + } + break; + + case 's': { + const char *s = va_arg( args, const char * ); + APPEND_STRING( buf, s ); + } + break; + + default: { + APPEND_STRING( buf, "<illegal format string %" ); + char buf2[2]; + buf2[0] = (char)( *s ); + buf2[1] = '\0'; + APPEND_STRING( buf, buf2 ); + buf2[0] = '\n'; + APPEND_STRING( buf, buf2 ); + } + } + + break; + + default: { + char buf2[2]; + buf2[0] = (char)( *s ); + buf2[1] = '\0'; + APPEND_STRING( buf, buf2 ); + } + } + s++; + } + + return len; +} + + #ifdef OS_ABAOS void __stdio_set_console( console_t *console ) { diff --git a/src/libc/stdio.h b/src/libc/stdio.h index 58c80b1..e32683f 100644 --- a/src/libc/stdio.h +++ b/src/libc/stdio.h @@ -18,6 +18,8 @@ int puts( const char *s ); int printf( const char *format, ... ); int vprintf( const char *format, va_list args ); +int snprintf( char *buf, size_t n, const char *format, ... ); +int vsnprintf( char *buf, size_t n, const char *format, va_list args ); #ifdef OS_ABAOS void __stdio_set_console( console_t *console ); |