more cleaning

sysexits/sysexits.c

@@ -0,0 +1,183 @@
+#include <ascii.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "usefulmacros.h"
+
+/* Thanks to u/smcameron on Reddit. */
+
+#define TAB_WIDTH 8
+
+/* Changing ENUM to DEFINE will make this output the traditional BSD header
+ * verbatim, without copyright notice. I don't have any fucking idea if that's
+ * a copyright violation, but let's keep this as ENUM to skirt by that little
+ * technicality.
+ * I implemented sysexits(3) in the enum method before reading the BSD 4.0
+ * source to see how they did it. */
+#define ENUM 1
+
+static char *program_name = "sysexits";
+
+//static const char comment_prefix[] = "/* ";
+static const char comment_prefix_ongoing[] = " * ";
+static const char comment_suffix[] = " */\n";
+
+static const char header_prefix[] =
+	"#ifndef _SYSEXITS_H\n"
+	"#\tdefine _SYSEXITS_H\n"
+	"enum{\n"
+;
+
+/* ASSUMPTIONS:
+ * - This array is always organized.
+ * - All characters in descriptions are one space wide.
+ * - The only whitespace in descriptions is ASCII_SP. */
+static const struct {
+	char *desc;
+	char *name;
+	int status;
+}sysexits[] = {
+	/* sysexit descriptions copied from FreeBSD's sysexits(3). */
+
+	{ "All is well.", /* except this one */
+	"EX_OK", 0 },
+
+	{ "The command was used incorrectly, e.g., with the wrong number of"
+	" arguments, a bad flag, a bad syntax in a parameter, or whatever.",
+	"EX_USAGE", 64 },
+
+	{ "The input data was incorrect in some way. This should only be used"
+	" for user's data and not system files.",
+	"EX_DATAERR", 65 },
+
+	{ "An input file (not a system file) did not exist or was not readable."
+	" This could also include errors like \"No message\" to a mailer (if it"
+	" cared to catch it).",
+	 "EX_NOINPUT", 66 },
+
+	{ "The user specified did not exist. This might be used for mail"
+	" addresses or remote logins.",
+	 "EX_NOUSER", 67 },
+
+	{ "The host specified did not exist. This is used in mail addresses or"
+	" network requests.",
+	 "EX_NOHOST", 68 },
+
+	{ "A service is unavailable. This can occur if a support program or"
+	" file does not exist. This can also be used as a catchall message"
+	" when something you wanted to do does not work, but you do not know"
+	" why.",
+	"EX_UNAVAILABLE", 69 },
+
+	{ "An internal software error has been detected. This should be limited"
+	" to non-operating system related errors as possible.",
+	"EX_SOFTWARE", 70 },
+
+	{ "An operating system error has been detected. This is intended to be"
+	" used for such things as \"cannot fork\", \"cannot create pipe\", or"
+	" the like. It includes things like getuid returning a user that does"
+	" not exist in the passwd file.",
+	"EX_OSERR", 71 },
+
+	{ "Some system file (e.g., /etc/passwd, /var/run/utx.active, etc.) does"
+	" not exist, cannot be opened, or has some sort of error (e.g., syntax"
+	" error).",
+	"EX_OSFILE", 72 },
+
+	{ "A (user specified) output file cannot be created.",
+	"EX_CANTCREAT", 73 },
+
+	{ "An error occurred while doing I/O on some file.",
+	"EX_IOERR", 74 },
+
+	{ "Temporary failure, indicating something that is not really an error."
+	" In sendmail, this means that a mailer (e.g.) could not create a"
+	" connection, and the request should be reattempted later.",
+	"EX_TEMPFAIL", 75 },
+
+	{ "The remote system returned something that was \"not possible\" during a"
+	" protocol exchange.",
+	"EX_PROTOCOL", 76 },
+
+	{ "You did not have sufficient permission to perform the operation."
+	" This is not intended for file system problems, which should use"
+	" EX_NOINPUT or EX_CANTCREAT, but rather for higher level"
+	" permissions.",
+	"EX_NOPERM", 77 },
+
+	{ "Something was found in an unconfigured or misconfigured state.",
+	"EX_CONFIG", 78 }
+};
+
+static const char header_suffix[] =
+	"};\n"
+	"#endif /* ifndef _SYSEXITS_H */\n"
+;
+
+static size_t i;
+
+static int findbyint(int status){
+	for(i = 0; i < ARRAYLEN(sysexits); ++i)
+		if(sysexits[i].status == status)
+			return i;
+	return -1;
+}
+
+static void output_comment(int fd, int indentation, int width, char *comment){
+	size_t word_start;
+	size_t line_start;
+
+	for(i = 0, line_start = 0, word_start = 0; ; ++i)
+		switch(comment[i]){
+		case '\0':
+			while(		i - line_start 
+					+ ARRAYLEN(comment_suffix)
+					+ indentation * TAB_WIDTH
+					> width){
+				i = word_start - 2; /* - current char, - space */
+				write(
+					fd, comment_prefix_ongoing,
+					ARRAYLEN(comment_prefix_ongoing)
+				);
+				write(fd, comment + line_start, i - line_start);
+				i += 2; /* + space, + next word char */
+				write(fd, "\n", 1);
+			}
+			write(fd, comment + line_start, i - line_start);
+			write(fd, comment_suffix, ARRAYLEN(comment_suffix));
+			break;
+		}
+
+	return;
+}
+
+static void output_header(void){
+	write(1, header_prefix, ARRAYLEN(header_prefix) - 1);
+	for(i = 0; i < ARRAYLEN(sysexits); ++i){
+		//output_comment(1, 1 * TAB_WIDTH, 80, sysexits[i].desc);
+		#ifdef ENUM
+		fprintf(stdout, "\t%s = %d%s",
+			sysexits[i].name,
+			sysexits[i].status,
+			i < ARRAYLEN(sysexits) - 1 ? ",\n" : "\n"
+		);
+		#endif /* ifdef ENUM */
+		#ifdef DEFINE
+		fprintf(stdout, "#\tdefine %s %d\n",
+			sysexits[i].name,
+			sysexits[i].status
+		);
+		#endif /* ifdef DEFINE */
+	}
+	fflush(stdout); /* Fixes actual issue. */
+	write(1, header_suffix, ARRAYLEN(header_suffix) - 1);
+}
+
+int main(int argc, char *argv[]){
+	if(argv[0] == NULL){
+		argv[0] = program_name;
+		++argc;
+	}
+
+	output_header();
+	return 0;
+}