return ((int) i);
}
-int strjoin (char *buffer, size_t buffer_size,
- char **fields, size_t fields_num,
- const char *sep)
-{
- size_t avail;
- char *ptr;
- size_t sep_len;
+int strjoin(char *buffer, size_t buffer_size, char **fields, size_t fields_num,
+ const char *sep) {
+ size_t avail = 0;
+ char *ptr = buffer;
+ size_t sep_len = 0;
- if ((buffer_size < 1) || (fields_num == 0))
- return (-1);
+ size_t buffer_req = 0;
- memset (buffer, 0, buffer_size);
- ptr = buffer;
- avail = buffer_size - 1;
+ if (((fields_num != 0) && (fields == NULL)) ||
+ ((buffer_size != 0) && (buffer == NULL)))
+ return (-EINVAL);
- sep_len = 0;
- if (sep != NULL)
- sep_len = strlen (sep);
+ if (buffer != NULL)
+ buffer[0] = 0;
- for (size_t i = 0; i < fields_num; i++)
- {
- size_t field_len;
+ if (buffer_size != 0)
+ avail = buffer_size - 1;
- if ((i > 0) && (sep_len > 0))
- {
- if (avail < sep_len)
- return (-1);
+ if (sep != NULL)
+ sep_len = strlen(sep);
- memcpy (ptr, sep, sep_len);
- ptr += sep_len;
- avail -= sep_len;
- }
+ for (size_t i = 0; i < fields_num; i++) {
+ size_t field_len = strlen(fields[i]);
- field_len = strlen (fields[i]);
- if (avail < field_len)
- return (-1);
+ if (i != 0)
+ buffer_req += sep_len;
+ buffer_req += field_len;
- memcpy (ptr, fields[i], field_len);
- ptr += field_len;
- avail -= field_len;
- }
+ if ((i != 0) && (sep_len > 0)) {
+ if (sep_len >= avail) {
+ /* prevent subsequent iterations from writing to the
+ * buffer. */
+ avail = 0;
+ continue;
+ }
+
+ memcpy(ptr, sep, sep_len);
+
+ ptr += sep_len;
+ avail -= sep_len;
+ }
+
+ if (field_len > avail)
+ field_len = avail;
+
+ memcpy(ptr, fields[i], field_len);
+ ptr += field_len;
+
+ avail -= field_len;
+ if (ptr != NULL)
+ *ptr = 0;
+ }
- assert (buffer[buffer_size - 1] == 0);
- return ((int) strlen (buffer));
+ return (int)buffer_req;
}
int escape_string (char *buffer, size_t buffer_size)
* is equivalent to the Perl built-in `join'.
*
* PARAMETERS
- * `dst' Buffer where the result is stored.
+ * `dst' Buffer where the result is stored. Can be NULL if you need to
+ * determine the required buffer size only.
* `dst_len' Length of the destination buffer. No more than this many
* bytes will be written to the memory pointed to by `dst',
- * including the trailing null-byte.
+ * including the trailing null-byte. Must be zero if dst is
+ * NULL.
* `fields' Array of strings to be joined.
* `fields_num' Number of elements in the `fields' array.
* `sep' String to be inserted between any two elements of `fields'.
* Instead of passing "" (empty string) one can pass NULL.
*
* RETURN VALUE
- * Returns the number of characters in `dst', NOT including the trailing
- * null-byte. If an error occurred (empty array or `dst' too small) a value
- * smaller than zero will be returned.
+ * Returns the number of characters in the resulting string, excluding a
+ * tailing null byte. If this value is greater than or equal to "dst_len", the
+ * result in "dst" is truncated (but still null terminated). On error a
+ * negative value is returned.
*/
int strjoin (char *dst, size_t dst_len, char **fields, size_t fields_num, const char *sep);
return (0);
}
-DEF_TEST(strjoin)
-{
- char buffer[16];
- char *fields[4];
- int status;
-
- fields[0] = "foo";
- fields[1] = "bar";
- fields[2] = "baz";
- fields[3] = "qux";
-
- status = strjoin (buffer, sizeof (buffer), fields, 2, "!");
- OK(status == 7);
- EXPECT_EQ_STR ("foo!bar", buffer);
-
- status = strjoin (buffer, sizeof (buffer), fields, 1, "!");
- OK(status == 3);
- EXPECT_EQ_STR ("foo", buffer);
-
- status = strjoin (buffer, sizeof (buffer), fields, 0, "!");
- OK(status < 0);
-
- status = strjoin (buffer, sizeof (buffer), fields, 2, "rcht");
- OK(status == 10);
- EXPECT_EQ_STR ("foorchtbar", buffer);
-
- status = strjoin (buffer, sizeof (buffer), fields, 4, "");
- OK(status == 12);
- EXPECT_EQ_STR ("foobarbazqux", buffer);
+DEF_TEST(strjoin) {
+ struct {
+ char **fields;
+ size_t fields_num;
+ char *separator;
+
+ int want_return;
+ char *want_buffer;
+ } cases
+ [] = {
+ /* Normal case. */
+ {(char *[]){"foo", "bar"}, 2, "!", 7, "foo!bar"},
+ /* One field only. */
+ {(char *[]){"foo"}, 1, "!", 3, "foo"},
+ /* No fields at all. */
+ {NULL, 0, "!", 0, ""},
+ /* Longer separator. */
+ {(char *[]){"foo", "bar"}, 2, "rcht", 10, "foorchtbar"},
+ /* Empty separator. */
+ {(char *[]){"foo", "bar"}, 2, "", 6, "foobar"},
+ /* NULL separator. */
+ {(char *[]){"foo", "bar"}, 2, NULL, 6, "foobar"},
+ /* buffer not large enough -> string is truncated. */
+ {(char *[]){"aaaaaa", "bbbbbb", "c!"}, 3, "-", 16, "aaaaaa-bbbbbb-c"},
+ /* buffer not large enough -> last field fills buffer completely. */
+ {(char *[]){"aaaaaaa", "bbbbbbb", "!"}, 3, "-", 17,
+ "aaaaaaa-bbbbbbb"},
+ /* buffer not large enough -> string does *not* end in separator. */
+ {(char *[]){"aaaa", "bbbb", "cccc", "!"}, 4, "-", 16,
+ "aaaa-bbbb-cccc"},
+ /* buffer not large enough -> string does not end with partial
+ separator. */
+ {(char *[]){"aaaaaa", "bbbbbb", "!"}, 3, "+-", 17, "aaaaaa+-bbbbbb"},
+ };
+
+ for (size_t i = 0; i < STATIC_ARRAY_SIZE(cases); i++) {
+ char buffer[16];
+ int status;
- status = strjoin (buffer, sizeof (buffer), fields, 4, "!");
- OK(status == 15);
- EXPECT_EQ_STR ("foo!bar!baz!qux", buffer);
+ memset(buffer, 0xFF, sizeof(buffer));
+ status = strjoin(buffer, sizeof(buffer), cases[i].fields,
+ cases[i].fields_num, cases[i].separator);
+ EXPECT_EQ_INT(cases[i].want_return, status);
+ EXPECT_EQ_STR(cases[i].want_buffer, buffer);
+ }
- fields[0] = "0123";
- fields[1] = "4567";
- fields[2] = "8901";
- fields[3] = "2345";
- status = strjoin (buffer, sizeof (buffer), fields, 4, "-");
- OK(status < 0);
+ /* use (NULL, 0) to determine required buffer size. */
+ EXPECT_EQ_INT(3, strjoin(NULL, 0, (char *[]){"a", "b"}, 2, "-"));
return (0);
}
projects / collectd.git / commitdiff