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-rw-r--r--regex/split.c316
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
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