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Diffstat (limited to 'nuttx/tools/b16.c')
-rw-r--r-- | nuttx/tools/b16.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/nuttx/tools/b16.c b/nuttx/tools/b16.c new file mode 100644 index 000000000..66d581ffa --- /dev/null +++ b/nuttx/tools/b16.c @@ -0,0 +1,121 @@ +/**************************************************************************** + * tools/b16.c + * + * Copyright (C) 2007-2012 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name NuttX nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <stdio.h> +#include <stdlib.h> + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +static void show_usage(const char *progname) +{ + fprintf(stderr, "\nUSAGE: %s <b16_t>|<float>\n", progname); + fprintf(stderr, "\nWhere:\n"); + fprintf(stderr, " <b16_t>:\n"); + fprintf(stderr, " A b16 fixed precision value in hexadecimal form: E.g., 0x00010000\n"); + fprintf(stderr, " Any value begininning with '0' will assumed by be hexadecimal format\n"); + fprintf(stderr, " <float>:\n"); + fprintf(stderr, " A floating value in standard form: E.g., 5.1\n"); + exit(EXIT_FAILURE); +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +int main(int argc, char **argv, char **envp) +{ + double fvalue; + unsigned long ulvalue; + long lvalue; + const char *str; + char *endptr; + + /* There must be exactly one argument */ + + if (argc != 2) + { + fprintf(stderr, "\nExpected a single argument\n"); + show_usage(argv[0]); + } + str = argv[1]; + + /* If the value begins with a zero, we will assume that it is a hexadecimal + * representation. + */ + + if (str[0] == '0') + { + endptr = NULL; + ulvalue = strtoul(str, &endptr, 16); + if (!endptr || *endptr != '\0') + { + fprintf(stderr, "\nHexadecimal argument not fully converted\n"); + show_usage(argv[0]); + } + + if (ulvalue >= 0x80000000) + { + lvalue = ~ulvalue + 1; + } + else + { + lvalue = ulvalue; + } + + fvalue = ((double)lvalue) / 65536.0; + printf("0x%08lx -> %10.5f\n", ulvalue, fvalue); + } + else + { + endptr = NULL; + fvalue = strtod(str, &endptr); + if (!endptr || *endptr != '\0') + { + fprintf(stderr, "\nFloating point argument not fully converted\n"); + show_usage(argv[0]); + } + + lvalue = 65536.0 * fvalue; + printf("%10.5f -> 0x%08lx\n", fvalue, lvalue); + } + + return 0; +} |