X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=mysql_selector.c;h=f8885f9a0f50ea0dd185e4cbecbc3a0ab17d1d0e;hp=91972e84ab0c179fba33129a811d171bd1c00021;hb=7598d7747435c4de259df09bdb82911ff893113d;hpb=f05276c4bf63c327da914ed4aae2568f38e47892

diff --git a/mysql_selector.c b/mysql_selector.c
index 91972e84..f8885f9a 100644
--- a/mysql_selector.c
+++ b/mysql_selector.c
@@ -28,6 +28,7 @@
 #include "db.h"
 #include <mysql/mysql.h>
 #include <mysql/mysql_version.h>
+#include <regex.h>
 #include "error.h"
 #include "net.h"
 #include "string.h"
@@ -39,6 +40,18 @@ extern struct misc_meta_data *mmd;
 
 static void *mysql_ptr = NULL;
 
+/**
+ * contains name/replacement pairs used by s_a_r_list()
+ *
+ * \sa s_a_r()
+ */
+struct para_macro {
+	/** the name of the macro */
+	const char *name;
+	/** the replacement text */
+	const char *replacement;
+};
+
 static struct para_macro macro_list[] = {
 	{	.name = "IS_N_SET",
 		.replacement = "(data.%s != '1')"
@@ -63,6 +76,93 @@ static struct para_macro macro_list[] = {
 	}
 };
 
+/**
+ * simple search and replace routine
+ *
+ * \param src source string
+ * \param macro_name the name of the macro
+ * \param replacement the replacement format string
+ *
+ * In \p src, replace each occurence of \p macro_name(arg) by the string
+ * determined by the \p replacement format string. \p replacement may (but
+ * needs not) contain a single string conversion specifier (%s) which gets
+ * replaced by \p arg.
+ *
+ * \return A string in which all matches in \p src are replaced, or \p NULL if
+ * an syntax error was encountered. Caller must free the result.
+ *
+ * \sa regcomp(3)
+ */
+__must_check __malloc static char *s_a_r(const char *src, const char* macro_name,
+		const char *replacement)
+{
+	regex_t preg;
+	size_t  nmatch = 1;
+	regmatch_t pmatch[1];
+	int eflags = 0;
+	char *dest = NULL;
+	const char *bufptr = src;
+
+	if (!macro_name || !replacement || !src)
+		return para_strdup(src);
+	regcomp(&preg, macro_name, 0);
+	while (regexec(&preg,  bufptr, nmatch, pmatch, eflags)
+			!= REG_NOMATCH) {
+		char *tmp, *arg, *o_bracket, *c_bracket;
+
+		o_bracket = strchr(bufptr + pmatch[0].rm_so, '(');
+		c_bracket = o_bracket? strchr(o_bracket, ')') : NULL;
+		if (!c_bracket)
+			goto out;
+		tmp = para_strdup(bufptr);
+		tmp[pmatch[0].rm_so] = '\0';
+		dest = para_strcat(dest, tmp);
+		free(tmp);
+
+		arg = para_strdup(o_bracket + 1);
+		arg[c_bracket - o_bracket - 1] = '\0';
+		tmp = make_message(replacement, arg);
+		free(arg);
+		dest = para_strcat(dest, tmp);
+		free(tmp);
+		bufptr = c_bracket;
+		bufptr++;
+	}
+	dest = para_strcat(dest, bufptr);
+//	PARA_DEBUG_LOG("%s: returning %s\n", __func__, dest);
+out:
+	regfree(&preg);
+	return dest;
+}
+
+/**
+ * replace a string according to a list of macros
+ *
+ * \param macro_list the array containing a macro/replacement pairs.
+ * \param src the source string
+ *
+ * This function just calls s_a_r() for each element of \p macro_list.
+ *
+ * \return \p NULL if one of the underlying calls to \p s_a_r returned \p NULL.
+ * Otherwise the completely expanded version of \p src is returned.
+ */
+__must_check __malloc static char *s_a_r_list(struct para_macro *macro_list, char *src)
+{
+	struct para_macro *mp = macro_list;
+	char *ret = NULL, *tmp = para_strdup(src);
+
+	while (mp->name) {
+		ret = s_a_r(tmp, mp->name, mp->replacement);
+		free(tmp);
+		if (!ret) /* syntax error */
+			return NULL;
+		tmp = ret;
+		mp++;
+	}
+	//PARA_DEBUG_LOG("%s: returning %s\n", __func__, dest);
+	return ret;
+}
+
 static int real_query(const char *query)
 {
 	if (!mysql_ptr)
@@ -2152,8 +2252,15 @@ static void shutdown_connection(void)
 /**
  * the init function of the mysql-based audio file selector
  *
- * Check the command line options and initialize all function pointers of \a db.
- * Connect to the mysql server and initialize the info string.
+ * \param db pointer to the struct to initialize
+ *
+ * Check the command line options and initialize all function pointers of \a
+ * db.  Connect to the mysql server and initialize the info string.
+ *
+ * \return This function returns success even if it could not connect
+ * to the mysql server. This is because the connect is expected to fail
+ * if there the paraslash database is not yet created. This gives the
+ * user a chance to send the "cdb" to create the database.
  *
  * \sa struct audio_file_selector, misc_meta_data::selector_info,
  * random_selector.c