config: add helper function for parsing key names
The config callback functions get keys of the general form: section.subsection.key (where the subsection may be contain arbitrary data, or may be missing). For matching keys without subsections, it is simple enough to call "strcmp". Matching keys with subsections is a little more complicated, and each callback does it in an ad-hoc way, usually involving error-prone pointer arithmetic. Let's provide a helper that keeps the pointer arithmetic all in one place. Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King committed
Jan 23, 2013 at 01:23 UTC
1b86bbb0ade4641c2da0dc74ebca1c09ec772bb4
2 files changed
+48
cache.h
+15
@@ -1164,6 +1164,21 @@ struct config_include_data {
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#define CONFIG_INCLUDE_INIT { 0 }
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extern int git_config_include(const char *name, const char *value, void *data);
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+/*
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+ * Match and parse a config key of the form:
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+ *
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+ * section.(subsection.)?key
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+ *
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+ * (i.e., what gets handed to a config_fn_t). The caller provides the section;
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+ * we return -1 if it does not match, 0 otherwise. The subsection and key
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+ * out-parameters are filled by the function (and subsection is NULL if it is
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+ * missing).
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+ */
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+extern int parse_config_key(const char *var,
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+ const char *section,
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+ const char **subsection, int *subsection_len,
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+ const char **key);
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+
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extern int committer_ident_sufficiently_given(void);
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extern int author_ident_sufficiently_given(void);
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config.c
+33
@@ -1667,3 +1667,36 @@ int config_error_nonbool(const char *var)
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{
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return error("Missing value for '%s'", var);
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}
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+
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+int parse_config_key(const char *var,
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+ const char *section,
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+ const char **subsection, int *subsection_len,
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+ const char **key)
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+{
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+ int section_len = strlen(section);
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+ const char *dot;
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+
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+ /* Does it start with "section." ? */
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+ if (prefixcmp(var, section) || var[section_len] != '.')
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+ return -1;
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+
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+ /*
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+ * Find the key; we don't know yet if we have a subsection, but we must
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+ * parse backwards from the end, since the subsection may have dots in
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+ * it, too.
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+ */
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+ dot = strrchr(var, '.');
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+ *key = dot + 1;
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+
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+ /* Did we have a subsection at all? */
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+ if (dot == var + section_len) {
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+ *subsection = NULL;
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+ *subsection_len = 0;
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+ }
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+ else {
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+ *subsection = var + section_len + 1;
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+ *subsection_len = dot - *subsection;
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+ }
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+
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+ return 0;
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+}