utils strbuf: Added sdb_strbuf_skip().

This function may be used to remove bytes and the beginning of the buffer.

diff --git a/src/include/utils/strbuf.h b/src/include/utils/strbuf.h
index ebbd9e3afff3dcc4bf143afa6019114c7cb4038f..af4a9ccd0251326386bb5ed2d946f6d5b55ecf66 100644 (file)
--- a/src/include/utils/strbuf.h
+++ b/src/include/utils/strbuf.h
@@ -136,6 +136,13 @@ sdb_strbuf_read(sdb_strbuf_t *strbuf, int fd, size_t n);
 ssize_t
 sdb_strbuf_chomp(sdb_strbuf_t *strbuf);
 
+/*
+ * sdb_strbuf_skip:
+ * Removes the first 'n' bytes from the buffer.
+ */
+void
+sdb_strbuf_skip(sdb_strbuf_t *strbuf, size_t n);
+
 /*
  * sdb_strbuf_string:
  * Returns the content of the string buffer. The caller may not modify the

diff --git a/src/utils/strbuf.c b/src/utils/strbuf.c
index bffcfc633c1b6669d391627ad67526d01e61c28f..2b64480c55fc5960c816f83ef3a6b3bf626c1faf 100644 (file)
--- a/src/utils/strbuf.c
+++ b/src/utils/strbuf.c
@@ -268,6 +268,24 @@ sdb_strbuf_chomp(sdb_strbuf_t *strbuf)
        return ret;
 } /* sdb_strbuf_chomp */
 
+void
+sdb_strbuf_skip(sdb_strbuf_t *strbuf, size_t n)
+{
+       if ((! strbuf) || (! n))
+               return;
+
+       if (n >= strbuf->pos) {
+               strbuf->string[0] = '\0';
+               strbuf->pos = 0;
+               return;
+       }
+
+       assert(n < strbuf->pos);
+       memmove(strbuf->string, strbuf->string + n, strbuf->pos - n);
+       strbuf->pos -= n;
+       strbuf->string[strbuf->pos] = '\0';
+} /* sdb_strbuf_skip */
+
 const char *
 sdb_strbuf_string(sdb_strbuf_t *strbuf)
 {

diff --git a/t/utils/strbuf_test.c b/t/utils/strbuf_test.c
index ad04b87e66a0f617812b7be96638f9f0155ebd9f..db392faad45bbeeb95a9f946be0b1bafbf4088af 100644 (file)
--- a/t/utils/strbuf_test.c
+++ b/t/utils/strbuf_test.c
@@ -304,6 +304,43 @@ START_TEST(test_sdb_strbuf_chomp)
 }
 END_TEST
 
+/* input is "1234567890" */
+static struct {
+       size_t n;
+       const char *expected;
+} skip_golden_data[] = {
+       { 0, "1234567890" },
+       { 1, "234567890" },
+       { 2, "34567890" },
+       { 9, "0" },
+       { 10, "" },
+       { 11, "" },
+       { 100, "" },
+};
+
+START_TEST(test_sdb_strbuf_skip)
+{
+       const char *input = "1234567890";
+       size_t i;
+
+       for (i = 0; i < SDB_STATIC_ARRAY_LEN(skip_golden_data); ++i) {
+               const char *check;
+
+               sdb_strbuf_sprintf(buf, input);
+               sdb_strbuf_skip(buf, skip_golden_data[i].n);
+
+               check = sdb_strbuf_string(buf);
+               fail_unless(!!check,
+                               "sdb_strbuf_string() = NULL (after skip); expected: string");
+
+               fail_unless(! strcmp(skip_golden_data[i].expected, check),
+                               "sdb_strbuf_skip('%s', %zu) did not skip correctly; "
+                               "got string '%s'; expected: '%s'", input,
+                               skip_golden_data[i].n, check, skip_golden_data[i].expected);
+       }
+}
+END_TEST
+
 static struct {
        const char *input;
        const char *expected;
@@ -370,6 +407,7 @@ util_strbuf_suite(void)
        tcase_add_test(tc, test_sdb_strbuf_memcpy);
        tcase_add_test(tc, test_sdb_strbuf_memappend);
        tcase_add_test(tc, test_sdb_strbuf_chomp);
+       tcase_add_test(tc, test_sdb_strbuf_skip);
        tcase_add_test(tc, test_sdb_strbuf_string);
        tcase_add_test(tc, test_sdb_strbuf_len);
        suite_add_tcase(s, tc);