diff options
Diffstat (limited to 'bitbang_spi.c')
-rw-r--r-- | bitbang_spi.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/bitbang_spi.c b/bitbang_spi.c index 0f1f7ed..abf5530 100644 --- a/bitbang_spi.c +++ b/bitbang_spi.c @@ -87,14 +87,16 @@ int bitbang_spi_send_command(unsigned int writecnt, unsigned int readcnt, static unsigned char *bufout = NULL; static unsigned char *bufin = NULL; static int oldbufsize = 0; - int bufsize = max(writecnt + readcnt, 260); + int bufsize; int i; /* Arbitrary size limitation here. We're only constrained by memory. */ if (writecnt > 65536 || readcnt > 65536) return SPI_INVALID_LENGTH; - if (bufsize != oldbufsize) { + bufsize = max(writecnt + readcnt, 260); + /* Never shrink. realloc() calls are expensive. */ + if (bufsize > oldbufsize) { bufout = realloc(bufout, bufsize); if (!bufout) { fprintf(stderr, "Out of memory!\n"); @@ -109,6 +111,7 @@ int bitbang_spi_send_command(unsigned int writecnt, unsigned int readcnt, free(bufout); exit(1); } + oldbufsize = bufsize; } memcpy(bufout, writearr, writecnt); |