<p>Neels Hofmeyr <strong>merged</strong> this change.</p><p><a href="https://gerrit.osmocom.org/13394">View Change</a></p><div style="white-space:pre-wrap">Approvals:
Harald Welte: Looks good to me, approved
Jenkins Builder: Verified
</div><pre style="font-family: monospace,monospace; white-space: pre-wrap;">add osmo_str_startswith()<br><br>Move from a static implementation in tdef_vty.c to utils.c, I also want to use<br>this in osmo-msc.<br><br>The point is that the telnet VTY allows unambiguous partly matches of keyword<br>args. For example, if I have a command definition of:<br><br> compare (apples|oranges)<br><br>then it is perfectly legal as for the vty parser to write only<br><br> compare app<br><br>One could expect the VTY to then pass the unambiguous match of "apples" to the<br>parsing function, but that is not the case.<br><br>Hence a VTY function implementation is faced with parsing a keyword of "app"<br>instead of the expected "apples".<br><br>This is actually a very widespread bug in our VTY implementations, which assume<br>that exactly one full keyword will always be found. I am now writing new<br>commands in a way that are able to manage only the starts of keywords.<br><br>Arguably, strstr(a, b) == a does the same thing, but it searches the entire<br>string unnecessarily.<br><br>Change-Id: Ib2ffb0e9a870dd52e081c7e66d8818057d159513<br>---<br>M include/osmocom/core/utils.h<br>M src/utils.c<br>M src/vty/tdef_vty.c<br>M tests/utils/utils_test.c<br>M tests/utils/utils_test.ok<br>5 files changed, 60 insertions(+), 11 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/include/osmocom/core/utils.h b/include/osmocom/core/utils.h</span><br><span>index 51e43ee..474e36c 100644</span><br><span>--- a/include/osmocom/core/utils.h</span><br><span>+++ b/include/osmocom/core/utils.h</span><br><span>@@ -237,4 +237,6 @@</span><br><span> #define OSMO_STRBUF_PRINTF(STRBUF, fmt, args...) \</span><br><span> OSMO_STRBUF_APPEND(STRBUF, snprintf, fmt, ##args)</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+bool osmo_str_startswith(const char *str, const char *startswith_str);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> /*! @} */</span><br><span>diff --git a/src/utils.c b/src/utils.c</span><br><span>index b8b4ef5..9ab990a 100644</span><br><span>--- a/src/utils.c</span><br><span>+++ b/src/utils.c</span><br><span>@@ -928,4 +928,18 @@</span><br><span> return (sum * 9) % 10 + '0';</span><br><span> }</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+/*! Compare start of a string.</span><br><span style="color: hsl(120, 100%, 40%);">+ * This is an optimisation of 'strstr(str, startswith_str) == str' because it doesn't search through the entire string.</span><br><span style="color: hsl(120, 100%, 40%);">+ * \param str (Longer) string to compare.</span><br><span style="color: hsl(120, 100%, 40%);">+ * \param startswith_str (Shorter) string to compare with the start of str.</span><br><span style="color: hsl(120, 100%, 40%);">+ * \return true iff the first characters of str fully match startswith_str or startswith_str is empty. */</span><br><span style="color: hsl(120, 100%, 40%);">+bool osmo_str_startswith(const char *str, const char *startswith_str)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!startswith_str || !*startswith_str)</span><br><span style="color: hsl(120, 100%, 40%);">+ return true;</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!str)</span><br><span style="color: hsl(120, 100%, 40%);">+ return false;</span><br><span style="color: hsl(120, 100%, 40%);">+ return strncmp(str, startswith_str, strlen(startswith_str)) == 0;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> /*! @} */</span><br><span>diff --git a/src/vty/tdef_vty.c b/src/vty/tdef_vty.c</span><br><span>index 28de21a..0dac2bf 100644</span><br><span>--- a/src/vty/tdef_vty.c</span><br><span>+++ b/src/vty/tdef_vty.c</span><br><span>@@ -247,16 +247,6 @@</span><br><span> /*! Singleton Tnnn groups definition as set by osmo_tdef_vty_groups_init(). */</span><br><span> static struct osmo_tdef_group *global_tdef_groups;</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">-/*! \return true iff the first characters of str fully match startswith_str or both are empty. */</span><br><span style="color: hsl(0, 100%, 40%);">-static bool startswith(const char *str, const char *startswith_str)</span><br><span style="color: hsl(0, 100%, 40%);">-{</span><br><span style="color: hsl(0, 100%, 40%);">- if (!startswith_str)</span><br><span style="color: hsl(0, 100%, 40%);">- return true;</span><br><span style="color: hsl(0, 100%, 40%);">- if (!str)</span><br><span style="color: hsl(0, 100%, 40%);">- return false;</span><br><span style="color: hsl(0, 100%, 40%);">- return strncmp(str, startswith_str, strlen(startswith_str)) == 0;</span><br><span style="color: hsl(0, 100%, 40%);">-}</span><br><span style="color: hsl(0, 100%, 40%);">-</span><br><span> DEFUN(show_timer, show_timer_cmd, "DYNAMIC", "DYNAMIC")</span><br><span> /* show timer [(alpha|beta|gamma)] [TNNNN] */</span><br><span> {</span><br><span>@@ -268,7 +258,7 @@</span><br><span> * like "softw" or "t" (which can also be ambiguous). */</span><br><span> </span><br><span> osmo_tdef_groups_for_each(g, global_tdef_groups) {</span><br><span style="color: hsl(0, 100%, 40%);">- if (!group_arg || startswith(g->name, group_arg))</span><br><span style="color: hsl(120, 100%, 40%);">+ if (!group_arg || osmo_str_startswith(g->name, group_arg))</span><br><span> osmo_tdef_vty_show_cmd(vty, g->tdefs, T_arg, "%s: ", g->name);</span><br><span> }</span><br><span> return CMD_SUCCESS;</span><br><span>diff --git a/tests/utils/utils_test.c b/tests/utils/utils_test.c</span><br><span>index 711d6e1..211b4d1 100644</span><br><span>--- a/tests/utils/utils_test.c</span><br><span>+++ b/tests/utils/utils_test.c</span><br><span>@@ -1014,6 +1014,33 @@</span><br><span> printf("(need %d chars, had size=63) %s\n", rc, buf);</span><br><span> }</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+static void startswith_test_str(const char *str, const char *startswith_str, bool expect_rc)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ bool rc = osmo_str_startswith(str, startswith_str);</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("osmo_str_startswith(%s, ", osmo_quote_str(str, -1));</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("%s) == %s\n", osmo_quote_str(startswith_str, -1), rc ? "true" : "false");</span><br><span style="color: hsl(120, 100%, 40%);">+ if (rc != expect_rc)</span><br><span style="color: hsl(120, 100%, 40%);">+ printf(" ERROR: EXPECTED %s\n", expect_rc ? "true" : "false");</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static void startswith_test()</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("\n%s()\n", __func__);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str(NULL, NULL, true);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str("", NULL, true);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str(NULL, "", true);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str("", "", true);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str("abc", NULL, true);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str("abc", "", true);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str(NULL, "abc", false);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str("", "abc", false);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str("abc", "a", true);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str("abc", "ab", true);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str("abc", "abc", true);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str("abc", "abcd", false);</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test_str("abc", "xyz", false);</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> int main(int argc, char **argv)</span><br><span> {</span><br><span> static const struct log_info log_info = {};</span><br><span>@@ -1032,5 +1059,6 @@</span><br><span> osmo_sockaddr_to_str_and_uint_test();</span><br><span> osmo_str_tolowupper_test();</span><br><span> strbuf_test();</span><br><span style="color: hsl(120, 100%, 40%);">+ startswith_test();</span><br><span> return 0;</span><br><span> }</span><br><span>diff --git a/tests/utils/utils_test.ok b/tests/utils/utils_test.ok</span><br><span>index 8fce9f1..5783eb1 100644</span><br><span>--- a/tests/utils/utils_test.ok</span><br><span>+++ b/tests/utils/utils_test.ok</span><br><span>@@ -340,3 +340,18 @@</span><br><span> (need 134 chars)</span><br><span> T minus 10 9 8 7 6 5 4 3 2 1 ... Lift off! -- T minus 10 9 8 7 6 5 4 3 2 1 ... Lift off! -- T minus 10 9 8 7 6 5 4 3 2 1 ... Lift off!</span><br><span> (need 134 chars, had size=63) T minus 10 9 8 7 6 5 4 3 2 1 ... Lift off! -- T minus 10 9 8 7</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+startswith_test()</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith(NULL, NULL) == true</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith("", NULL) == true</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith(NULL, "") == true</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith("", "") == true</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith("abc", NULL) == true</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith("abc", "") == true</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith(NULL, "abc") == false</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith("", "abc") == false</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith("abc", "a") == true</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith("abc", "ab") == true</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith("abc", "abc") == true</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith("abc", "abcd") == false</span><br><span style="color: hsl(120, 100%, 40%);">+osmo_str_startswith("abc", "xyz") == false</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.osmocom.org/13394">change 13394</a>. 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<div style="display:none"> Gerrit-Project: libosmocore </div>
<div style="display:none"> Gerrit-Branch: master </div>
<div style="display:none"> Gerrit-MessageType: merged </div>
<div style="display:none"> Gerrit-Change-Id: Ib2ffb0e9a870dd52e081c7e66d8818057d159513 </div>
<div style="display:none"> Gerrit-Change-Number: 13394 </div>
<div style="display:none"> Gerrit-PatchSet: 3 </div>
<div style="display:none"> Gerrit-Owner: Neels Hofmeyr <nhofmeyr@sysmocom.de> </div>
<div style="display:none"> Gerrit-Reviewer: Harald Welte <laforge@gnumonks.org> </div>
<div style="display:none"> Gerrit-Reviewer: Jenkins Builder (1000002) </div>
<div style="display:none"> Gerrit-Reviewer: Max <suraev@alumni.ntnu.no> </div>
<div style="display:none"> Gerrit-Reviewer: Neels Hofmeyr <nhofmeyr@sysmocom.de> </div>