Initial revision

1 files changed, 316 insertions, 0 deletions

diff --git a/regex/split.c b/regex/split.c
new file mode 100644
index 0000000..188bdb7
--- /dev/null
+++ b/regex/split.c
@@ -0,0 +1,316 @@
+#include <stdio.h>
+#include <string.h>
+
+/*
+ - split - divide a string into fields, like awk split()
+ = int split(char *string, char *fields[], int nfields, char *sep);
+ */
+int				/* number of fields, including overflow */
+split(string, fields, nfields, sep)
+char *string;
+char *fields[];			/* list is not NULL-terminated */
+int nfields;			/* number of entries available in fields[] */
+char *sep;			/* "" white, "c" single char, "ab" [ab]+ */
+{
+	register char *p = string;
+	register char c;			/* latest character */
+	register char sepc = sep[0];
+	register char sepc2;
+	register int fn;
+	register char **fp = fields;
+	register char *sepp;
+	register int trimtrail;
+
+	/* white space */
+	if (sepc == '\0') {
+		while ((c = *p++) == ' ' || c == '\t')
+			continue;
+		p--;
+		trimtrail = 1;
+		sep = " \t";	/* note, code below knows this is 2 long */
+		sepc = ' ';
+	} else
+		trimtrail = 0;
+	sepc2 = sep[1];		/* now we can safely pick this up */
+
+	/* catch empties */
+	if (*p == '\0')
+		return(0);
+
+	/* single separator */
+	if (sepc2 == '\0') {
+		fn = nfields;
+		for (;;) {
+			*fp++ = p;
+			fn--;
+			if (fn == 0)
+				break;
+			while ((c = *p++) != sepc)
+				if (c == '\0')
+					return(nfields - fn);
+			*(p-1) = '\0';
+		}
+		/* we have overflowed the fields vector -- just count them */
+		fn = nfields;
+		for (;;) {
+			while ((c = *p++) != sepc)
+				if (c == '\0')
+					return(fn);
+			fn++;
+		}
+		/* not reached */
+	}
+
+	/* two separators */
+	if (sep[2] == '\0') {
+		fn = nfields;
+		for (;;) {
+			*fp++ = p;
+			fn--;
+			while ((c = *p++) != sepc && c != sepc2)
+				if (c == '\0') {
+					if (trimtrail && **(fp-1) == '\0')
+						fn++;
+					return(nfields - fn);
+				}
+			if (fn == 0)
+				break;
+			*(p-1) = '\0';
+			while ((c = *p++) == sepc || c == sepc2)
+				continue;
+			p--;
+		}
+		/* we have overflowed the fields vector -- just count them */
+		fn = nfields;
+		while (c != '\0') {
+			while ((c = *p++) == sepc || c == sepc2)
+				continue;
+			p--;
+			fn++;
+			while ((c = *p++) != '\0' && c != sepc && c != sepc2)
+				continue;
+		}
+		/* might have to trim trailing white space */
+		if (trimtrail) {
+			p--;
+			while ((c = *--p) == sepc || c == sepc2)
+				continue;
+			p++;
+			if (*p != '\0') {
+				if (fn == nfields+1)
+					*p = '\0';
+				fn--;
+			}
+		}
+		return(fn);
+	}
+
+	/* n separators */
+	fn = 0;
+	for (;;) {
+		if (fn < nfields)
+			*fp++ = p;
+		fn++;
+		for (;;) {
+			c = *p++;
+			if (c == '\0')
+				return(fn);
+			sepp = sep;
+			while ((sepc = *sepp++) != '\0' && sepc != c)
+				continue;
+			if (sepc != '\0')	/* it was a separator */
+				break;
+		}
+		if (fn < nfields)
+			*(p-1) = '\0';
+		for (;;) {
+			c = *p++;
+			sepp = sep;
+			while ((sepc = *sepp++) != '\0' && sepc != c)
+				continue;
+			if (sepc == '\0')	/* it wasn't a separator */
+				break;
+		}
+		p--;
+	}
+
+	/* not reached */
+}
+
+#ifdef TEST_SPLIT
+
+
+/*
+ * test program
+ * pgm		runs regression
+ * pgm sep	splits stdin lines by sep
+ * pgm str sep	splits str by sep
+ * pgm str sep n	splits str by sep n times
+ */
+int
+main(argc, argv)
+int argc;
+char *argv[];
+{
+	char buf[512];
+	register int n;
+#	define	MNF	10
+	char *fields[MNF];
+
+	if (argc > 4)
+		for (n = atoi(argv[3]); n > 0; n--) {
+			(void) strcpy(buf, argv[1]);
+		}
+	else if (argc > 3)
+		for (n = atoi(argv[3]); n > 0; n--) {
+			(void) strcpy(buf, argv[1]);
+			(void) split(buf, fields, MNF, argv[2]);
+		}
+	else if (argc > 2)
+		dosplit(argv[1], argv[2]);
+	else if (argc > 1)
+		while (fgets(buf, sizeof(buf), stdin) != NULL) {
+			buf[strlen(buf)-1] = '\0';	/* stomp newline */
+			dosplit(buf, argv[1]);
+		}
+	else
+		regress();
+
+	exit(0);
+}
+
+dosplit(string, seps)
+char *string;
+char *seps;
+{
+#	define	NF	5
+	char *fields[NF];
+	register int nf;
+
+	nf = split(string, fields, NF, seps);
+	print(nf, NF, fields);
+}
+
+print(nf, nfp, fields)
+int nf;
+int nfp;
+char *fields[];
+{
+	register int fn;
+	register int bound;
+
+	bound = (nf > nfp) ? nfp : nf;
+	printf("%d:\t", nf);
+	for (fn = 0; fn < bound; fn++)
+		printf("\"%s\"%s", fields[fn], (fn+1 < nf) ? ", " : "\n");
+}
+
+#define	RNF	5		/* some table entries know this */
+struct {
+	char *str;
+	char *seps;
+	int nf;
+	char *fi[RNF];
+} tests[] = {
+	"",		" ",	0,	{ "" },
+	" ",		" ",	2,	{ "", "" },
+	"x",		" ",	1,	{ "x" },
+	"xy",		" ",	1,	{ "xy" },
+	"x y",		" ",	2,	{ "x", "y" },
+	"abc def  g ",	" ",	5,	{ "abc", "def", "", "g", "" },
+	"  a bcd",	" ",	4,	{ "", "", "a", "bcd" },
+	"a b c d e f",	" ",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d ",	" ",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		" _",	0,	{ "" },
+	" ",		" _",	2,	{ "", "" },
+	"x",		" _",	1,	{ "x" },
+	"x y",		" _",	2,	{ "x", "y" },
+	"ab _ cd",	" _",	2,	{ "ab", "cd" },
+	" a_b  c ",	" _",	5,	{ "", "a", "b", "c", "" },
+	"a b c_d e f",	" _",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d ",	" _",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		" _~",	0,	{ "" },
+	" ",		" _~",	2,	{ "", "" },
+	"x",		" _~",	1,	{ "x" },
+	"x y",		" _~",	2,	{ "x", "y" },
+	"ab _~ cd",	" _~",	2,	{ "ab", "cd" },
+	" a_b  c~",	" _~",	5,	{ "", "a", "b", "c", "" },
+	"a b_c d~e f",	" _~",	6,	{ "a", "b", "c", "d", "e f" },
+	"~a b c d ",	" _~",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		" _~-",	0,	{ "" },
+	" ",		" _~-",	2,	{ "", "" },
+	"x",		" _~-",	1,	{ "x" },
+	"x y",		" _~-",	2,	{ "x", "y" },
+	"ab _~- cd",	" _~-",	2,	{ "ab", "cd" },
+	" a_b  c~",	" _~-",	5,	{ "", "a", "b", "c", "" },
+	"a b_c-d~e f",	" _~-",	6,	{ "a", "b", "c", "d", "e f" },
+	"~a-b c d ",	" _~-",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		"  ",	0,	{ "" },
+	" ",		"  ",	2,	{ "", "" },
+	"x",		"  ",	1,	{ "x" },
+	"xy",		"  ",	1,	{ "xy" },
+	"x y",		"  ",	2,	{ "x", "y" },
+	"abc def  g ",	"  ",	4,	{ "abc", "def", "g", "" },
+	"  a bcd",	"  ",	3,	{ "", "a", "bcd" },
+	"a b c d e f",	"  ",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d ",	"  ",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		"",	0,	{ "" },
+	" ",		"",	0,	{ "" },
+	"x",		"",	1,	{ "x" },
+	"xy",		"",	1,	{ "xy" },
+	"x y",		"",	2,	{ "x", "y" },
+	"abc def  g ",	"",	3,	{ "abc", "def", "g" },
+	"\t a bcd",	"",	2,	{ "a", "bcd" },
+	"  a \tb\t c ",	"",	3,	{ "a", "b", "c" },
+	"a b c d e ",	"",	5,	{ "a", "b", "c", "d", "e" },
+	"a b\tc d e f",	"",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d e f ",	"",	6,	{ "a", "b", "c", "d", "e f " },
+
+	NULL,		NULL,	0,	{ NULL },
+};
+
+regress()
+{
+	char buf[512];
+	register int n;
+	char *fields[RNF+1];
+	register int nf;
+	register int i;
+	register int printit;
+	register char *f;
+
+	for (n = 0; tests[n].str != NULL; n++) {
+		(void) strcpy(buf, tests[n].str);
+		fields[RNF] = NULL;
+		nf = split(buf, fields, RNF, tests[n].seps);
+		printit = 0;
+		if (nf != tests[n].nf) {
+			printf("split `%s' by `%s' gave %d fields, not %d\n",
+				tests[n].str, tests[n].seps, nf, tests[n].nf);
+			printit = 1;
+		} else if (fields[RNF] != NULL) {
+			printf("split() went beyond array end\n");
+			printit = 1;
+		} else {
+			for (i = 0; i < nf && i < RNF; i++) {
+				f = fields[i];
+				if (f == NULL)
+					f = "(NULL)";
+				if (strcmp(f, tests[n].fi[i]) != 0) {
+					printf("split `%s' by `%s', field %d is `%s', not `%s'\n",
+						tests[n].str, tests[n].seps,
+						i, fields[i], tests[n].fi[i]);
+					printit = 1;
+				}
+			}
+		}
+		if (printit)
+			print(nf, RNF, fields);
+	}
+}
+#endif