diff options
Diffstat (limited to 'tools/lz/options.c')
| -rw-r--r-- | tools/lz/options.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/tools/lz/options.c b/tools/lz/options.c new file mode 100644 index 000000000..8e5d05a7b --- /dev/null +++ b/tools/lz/options.c @@ -0,0 +1,141 @@ +#include "proto.h" + +struct options get_options (int argc, char ** argv) { + struct options result = {.input = NULL, .output = NULL, .mode = 0, .alignment = 0, .method = COMPRESSION_METHODS}; + const char * program_name = *argv; + int compressor = -1; + if (argc == 1) usage(program_name); + for (argv ++; *argv; argv ++) { + if (**argv != '-') break; + if (!1[*argv]) break; + if (!strcmp(*argv, "--")) { + argv ++; + break; + } else if (!(strcmp(*argv, "--text") && strcmp(*argv, "-t"))) + result.mode = 1; + else if (!(strcmp(*argv, "--binary") && strcmp(*argv, "-b"))) + result.mode = 0; + else if (!(strcmp(*argv, "--uncompress") && strcmp(*argv, "-u"))) + result.mode = 2; + else if (!(strcmp(*argv, "--dump") && strcmp(*argv, "-d"))) + result.mode = 3; + else if (!(strcmp(*argv, "--align") && strncmp(*argv, "-a", 2))) + result.alignment = parse_numeric_option_argument(&argv, 12); + else if (!(strcmp(*argv, "--method") && strncmp(*argv, "-m", 2))) + result.method = parse_numeric_option_argument(&argv, COMPRESSION_METHODS - 1); + else if (!(strcmp(*argv, "--compressor") && strncmp(*argv, "-c", 2))) + compressor = parse_compressor_option_argument(&argv); + else if (!(strcmp(*argv, "--optimize") && strcmp(*argv, "-o"))) { + result.method = COMPRESSION_METHODS; + compressor = -1; + } else if (!(strcmp(*argv, "--help") && strcmp(*argv, "-?"))) + usage(program_name); + else if (!(strcmp(*argv, "--list") && strcmp(*argv, "-l"))) + list_compressors(); + else + error_exit(3, "unknown option: %s", *argv); + } + if (compressor >= 0) { + if (result.method >= COMPRESSION_METHODS) result.method = 0; + if (result.method >= compressors[compressor].methods) + error_exit(3, "method for the %s compressor must be between 0 and %u", compressors[compressor].name, compressors[compressor].methods - 1); + while (compressor > 0) result.method += compressors[-- compressor].methods; + } + if (*argv) { + if (strcmp(*argv, "-")) result.input = *argv; + if (*(++ argv)) { + if (argv[1]) error_exit(3, "too many command-line arguments"); + if (strcmp(*argv, "-")) result.output = *argv; + } + } + return result; +} + +unsigned parse_numeric_option_argument (char *** alp, unsigned limit) { + const char * option; + const char * value = get_argument_for_option(alp, &option); + char * error; + unsigned long result = strtoul(value, &error, 10); + if (*error) error_exit(3, "invalid argument to option %s", option); + if (result > limit) error_exit(3, "argument to option %s must be between 0 and %u", option, limit); + return result; +} + +int parse_compressor_option_argument (char *** alp) { + const char * name = get_argument_for_option(alp, NULL); + if (!strcmp(name, "*")) return -1; + int result = -1; + unsigned length = strlen(name); + const struct compressor * compressor; + for (compressor = compressors; compressor -> name; compressor ++) { + if (strncmp(name, compressor -> name, length)) continue; + if (result >= 0) error_exit(3, "ambiguous compressor prefix: %s", name); + result = compressor - compressors; + } + if (result < 0) error_exit(3, "unknown compressor: %s", name); + return result; +} + +const char * get_argument_for_option (char *** alp, const char ** option_name) { + // alp: argument list pointer (i.e., address of the current value of argv after indexing) + // will point at the last consumed argument on exit (since the caller will probably increment it once more) + const char * option; + const char * result; + if (1[**alp] == '-') { + option = *((*alp) ++); + result = **alp; + } else { + option_name_buffer[1] = 1[**alp]; + option = option_name_buffer; + result = **alp + 2; + } + if (!(result && *result)) error_exit(3, "option %s requires an argument", option); + if (option_name) *option_name = option; + return result; +} + +noreturn usage (const char * program_name) { + fprintf(stderr, "Usage: %s [<options>] [<source file> [<output>]]\n\n", program_name); + fputs("Execution mode:\n", stderr); + fputs(" -b, --binary Output the command stream as binary data (default).\n", stderr); + fputs(" -t, --text Output the command stream as text.\n", stderr); + fputs(" -u, --uncompress Process a compressed file and output the original data.\n", stderr); + fputs(" -d, --dump Process a compressed file and dump the command stream as\n", stderr); + fputs(" text (as if compressed with the --text option).\n", stderr); + fputs(" -l, --list List compressors and their method numbers.\n", stderr); + fputs(" -?, --help Print this help text and exit.\n", stderr); + fputs("Compression options:\n", stderr); + fputs(" -o, --optimize Use the best combination of compression\n", stderr); + fputs(" methods available (default).\n", stderr); + fputs(" -m<number>, --method <number> Use only one specific compression method.\n", stderr); + fprintf(stderr, " Valid method numbers are between 0 and %u.\n", COMPRESSION_METHODS - 1); + fputs(" -c<name>, --compressor <name> Use the specified compressor: the method\n", stderr); + fputs(" number will be relative to that compressor.\n", stderr); + fputs(" Any prefix of the compressor name may be\n", stderr); + fputs(" specified. Use * to indicate any compressor.\n", stderr); + fputs(" -a<number>, --align <number> Pad the compressed output with zeros until\n", stderr); + fputs(" the size has the specified number of low bits\n", stderr); + fputs(" cleared (default: 0).\n", stderr); + fputs("The source and output filenames can be given as - (or omitted) to use standard\n", stderr); + fputs("input and output. Use -- to indicate that subsequent arguments are file names.\n", stderr); + exit(3); +} + +noreturn list_compressors (void) { + const struct compressor * compressor; + unsigned current, length = 10; + for (compressor = compressors; compressor -> name; compressor ++) if ((current = strlen(compressor -> name)) > length) length = current; + fprintf(stderr, "%-*s Offset Methods\n", length, "Compressor"); + for (current = 0; current < length; current ++) putc('-', stderr); + fputs(" ------ -------\n", stderr); + current = 0; + for (compressor = compressors; compressor -> name; compressor ++) { + fprintf(stderr, "%-*s %6u %7u\n", length, compressor -> name, current, compressor -> methods); + current += compressor -> methods; + } + putc('\n', stderr); + fputs("Note: the offset indicates the compressor's lowest method number when the\n", stderr); + fputs("--compressor option is not given. When that option is used, every compressor's\n", stderr); + fputs("methods are numbered from zero.\n", stderr); + exit(3); +} |