[ccan] [PATCH 09/11] bytestring: Split bytestrings by a string delimiter
David Gibson
david at gibson.dropbear.id.au
Sun Oct 12 03:43:34 AEDT 2014
This introduces the functions bytestring_splitstr_first() and
bytestring_splitstr_next() which can be used to iterate through substrings
of a bytestring separated by a specified substring.
Signed-off-by: David Gibson <david at gibson.dropbear.id.au>
---
ccan/bytestring/bytestring.c | 42 ++++++++++++++++++++++++++++++++++++++++++
ccan/bytestring/bytestring.h | 28 ++++++++++++++++++++++++++++
ccan/bytestring/test/run.c | 35 ++++++++++++++++++++++++++++++++++-
3 files changed, 104 insertions(+), 1 deletion(-)
diff --git a/ccan/bytestring/bytestring.c b/ccan/bytestring/bytestring.c
index 7f5f46a..67d7a55 100644
--- a/ccan/bytestring/bytestring.c
+++ b/ccan/bytestring/bytestring.c
@@ -104,3 +104,45 @@ struct bytestring bytestring_splitchrs_next(struct bytestring whole,
return _splitchrs(whole, delim, (prev.ptr - whole.ptr) + prev.len + 1);
}
+
+static struct bytestring _splitstr(struct bytestring whole,
+ struct bytestring delim, size_t start)
+{
+ struct bytestring remainder, nextdelim;
+
+ assert(start <= whole.len);
+
+ remainder = bytestring_slice(whole, start, whole.len);
+ nextdelim = bytestring_bytestring(remainder, delim);
+ if (nextdelim.ptr)
+ return bytestring_slice(whole, start,
+ nextdelim.ptr - whole.ptr);
+ else
+ return remainder;
+}
+
+struct bytestring bytestring_splitstr_first(struct bytestring whole,
+ struct bytestring delim)
+{
+ if (whole.len == 0)
+ return bytestring_NULL;
+
+ return _splitstr(whole, delim, 0);
+}
+
+struct bytestring bytestring_splitstr_next(struct bytestring whole,
+ struct bytestring delim,
+ struct bytestring prev)
+{
+ if (!prev.ptr)
+ return bytestring_NULL;
+
+ /* prev has to be a substring of whole */
+ assert(prev.ptr >= whole.ptr);
+
+ if ((prev.ptr + prev.len) == (whole.ptr + whole.len))
+ return bytestring_NULL;
+
+ return _splitstr(whole, delim,
+ (prev.ptr - whole.ptr) + prev.len + delim.len);
+}
diff --git a/ccan/bytestring/bytestring.h b/ccan/bytestring/bytestring.h
index a444d3d..f0dcdf9 100644
--- a/ccan/bytestring/bytestring.h
+++ b/ccan/bytestring/bytestring.h
@@ -257,4 +257,32 @@ struct bytestring bytestring_splitchrs_next(struct bytestring whole,
(_s).ptr; \
(_s) = bytestring_splitchrs_next((_w), (_delim), (_s)))
+/**
+ * bytestring_splitstr_first - split a bytestring on a delimiter string
+ * @whole: a bytestring
+ * @delim: delimiter substring
+ *
+ * Returns the first substring of @whole delimited by the substring in
+ * @delim.
+ */
+struct bytestring bytestring_splitstr_first(struct bytestring whole,
+ struct bytestring delim);
+
+/**
+ * bytestring_splitstr_next - split a bytestring on a delimiter string
+ * @whole: a bytestring
+ * @delim: delimiter string
+ * @prev: last substring
+ *
+ * Returns the next @delim delimited substring of @whole after @prev.
+ */
+struct bytestring bytestring_splitstr_next(struct bytestring whole,
+ struct bytestring delim,
+ struct bytestring prev);
+
+#define bytestring_foreach_splitstr(_s, _w, _delim) \
+ for ((_s) = bytestring_splitstr_first((_w), (_delim)); \
+ (_s).ptr; \
+ (_s) = bytestring_splitstr_next((_w), (_delim), (_s)))
+
#endif /* CCAN_BYTESTRING_H_ */
diff --git a/ccan/bytestring/test/run.c b/ccan/bytestring/test/run.c
index b40c1f8..206cffb 100644
--- a/ccan/bytestring/test/run.c
+++ b/ccan/bytestring/test/run.c
@@ -17,7 +17,7 @@ int main(void)
int n;
/* This is how many tests you plan to run */
- plan_tests(102);
+ plan_tests(119);
bs = bytestring(str1, sizeof(str1) - 1);
ok1(bs.ptr == str1);
@@ -190,6 +190,39 @@ int main(void)
}
ok1(n == 6);
+ bs7 = bytestring_splitstr_first(bs, BYTESTRING("t "));
+ ok1(bs7.ptr == bs.ptr);
+ ok1(bytestring_eq(bs7, BYTESTRING("tes")));
+ bs7 = bytestring_splitstr_next(bs, BYTESTRING("t "), bs7);
+ ok1(bs7.ptr == bs.ptr + 5);
+ ok1(bytestring_eq(bs7, BYTESTRING("string")));
+ bs7 = bytestring_splitstr_next(bs, BYTESTRING("t "), bs7);
+ ok1(!bs7.ptr);
+ bs7 = bytestring_splitstr_next(bs, BYTESTRING("t "), bs7);
+ ok1(!bs7.ptr);
+
+ bs7 = bytestring_splitstr_first(bs2, BYTESTRING("abc"));
+ ok1(bs7.ptr == bs2.ptr);
+ ok1(bs7.len == 0);
+ bs7 = bytestring_splitstr_next(bs2, BYTESTRING("abc"), bs7);
+ ok1(bs7.ptr == bs2.ptr + 3);
+ ok1(bytestring_eq(bs7, BYTESTRING("\0def")));
+ bs7 = bytestring_splitstr_next(bs2, BYTESTRING("t "), bs7);
+ ok1(!bs7.ptr);
+ bs7 = bytestring_splitstr_next(bs2, BYTESTRING("t "), bs7);
+ ok1(!bs7.ptr);
+
+ bs7 = bytestring_splitstr_first(BYTESTRING(""), BYTESTRING(""));
+ ok1(!bs7.ptr);
+
+ n = 0;
+ bytestring_foreach_splitstr(bs7, BYTESTRING("foofoo"),
+ BYTESTRING("foo")) {
+ n++;
+ ok1(bs7.ptr && !bs7.len);
+ }
+ ok1(n == 3);
+
/* This exits depending on whether all tests passed */
return exit_status();
}
--
1.9.3
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