Feature: Added new resource match system

src/Makefile.am

@@ -7,6 +7,7 @@ bin_PROGRAMS = icecast
 noinst_HEADERS = \
     icecasttypes.h \
     admin.h \
+    resourcematch.h \
     main.h \
     cfgfile.h \
     logging.h \
@@ -69,6 +70,7 @@ icecast_SOURCES = \
     xslt.c \
     fserve.c \
     admin.c \
+    resourcematch.c \
     md5.c \
     matchfile.c \
     tls.c \

src/resourcematch.c

+/* Icecast
+ *
+ * This program is distributed under the GNU General Public License, version 2.
+ * A copy of this license is included with this source.
+ *
+ * Copyright 2018,      Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+
+#include <stdlib.h>
+#include <errno.h>
+
+#include "resourcematch.h"
+
+static size_t count_groups(const char *pattern)
+{
+    size_t ret = 0;
+
+    while (*pattern) {
+        for (; *pattern && *pattern != '%'; pattern++);
+
+        if (!*pattern) {
+            return ret;
+        }
+
+        pattern++;
+
+        if (!*pattern)
+            return ret;
+
+        if (*pattern != '%')
+            ret++;
+
+        pattern++;
+    }
+
+    return ret;
+}
+
+static resourcematch_extract_t * allocate_extract(const char *pattern)
+{
+    size_t groups = count_groups(pattern);
+    resourcematch_extract_t *ret;
+
+    ret = calloc(1, sizeof(*ret));
+    if (!ret)
+        return NULL;
+
+    ret->groups = groups;
+    ret->group = calloc(groups, sizeof(*ret->group));
+
+    return ret;
+}
+
+static void strip_common_prefix(const char **pattern, const char **string)
+{
+    const char *p = *pattern;
+    const char *s = *string;
+
+    for (; *p && *p != '%' && *p == *s; p++, s++);
+
+    *pattern = p;
+    *string = s;
+}
+
+static inline void setup_group(resourcematch_extract_t *extract, size_t idx, char type)
+{
+    if (!extract)
+        return;
+
+    extract->group[idx].type = type;
+    extract->group[idx].raw = NULL;
+}
+
+static inline resourcematch_result_t match_lli(const char **string, resourcematch_extract_t *extract, size_t idx, int base)
+{
+    long long int ret;
+    char *endptr;
+
+    errno = 0;
+    ret = strtoll(*string, &endptr, base);
+    if (errno != 0)
+        return RESOURCEMATCH_ERROR;
+
+    if (extract) {
+        extract->group[idx].result.lli = ret;
+    }
+
+    *string = endptr;
+
+    return RESOURCEMATCH_MATCH;
+}
+
+resourcematch_result_t resourcematch_match(const char *pattern, const char *string, resourcematch_extract_t **extract)
+{
+    resourcematch_result_t ret;
+    resourcematch_extract_t *matches = NULL;
+    size_t idx = 0;
+
+    if (!pattern || !string)
+        return RESOURCEMATCH_ERROR;
+
+    if (extract) {
+        matches = allocate_extract(pattern);
+        if (!matches)
+            return RESOURCEMATCH_NOMATCH;
+    }
+
+    while (1) {
+        strip_common_prefix(&pattern, &string);
+
+        if (!*pattern && !*string) {
+            if (extract)
+                *extract = matches;
+
+            return RESOURCEMATCH_MATCH;
+        } else if (!*pattern || !*string) {
+            if (extract)
+                resourcematch_extract_free(matches);
+
+            return RESOURCEMATCH_NOMATCH;
+        }
+
+        if (*pattern != '%') {
+            if (extract)
+                resourcematch_extract_free(matches);
+
+            return RESOURCEMATCH_NOMATCH;
+        }
+
+        pattern++;
+
+        switch (*pattern) {
+            case '%':
+                if (*string == '%') {
+                    string++;
+                } else {
+                    if (extract)
+                        resourcematch_extract_free(matches);
+
+                    return RESOURCEMATCH_NOMATCH;
+                }
+            break;
+#define _test_int(type,base) \
+            case (type): \
+                setup_group(matches, idx, *pattern); \
+\
+                ret = match_lli(&string, matches, idx, (base)); \
+                if (ret != RESOURCEMATCH_MATCH) { \
+                    if (extract) \
+                        resourcematch_extract_free(matches); \
+\
+                    return ret; \
+                } \
+                idx++; \
+            break;
+
+            _test_int('i', 0);
+            _test_int('d', 10);
+            _test_int('x', 16);
+            _test_int('o', 8);
+
+            default:
+                if (extract)
+                    resourcematch_extract_free(matches);
+
+                return RESOURCEMATCH_ERROR;
+            break;
+        }
+
+        pattern++;
+    }
+}
+
+void resourcematch_extract_free(resourcematch_extract_t *extract)
+{
+    size_t i;
+
+    if (!extract)
+        return;
+
+    for (i = 0; i < extract->groups; i++) {
+        free(extract->group[i].raw);
+    }
+
+    free(extract->group);
+    free(extract);
+}

src/resourcematch.h

+/* Icecast
+ *
+ * This program is distributed under the GNU General Public License, version 2.
+ * A copy of this license is included with this source.
+ *
+ * Copyright 2018,      Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
+ */
+
+#ifndef __RESOURCEMATCH_H__
+#define __RESOURCEMATCH_H__
+
+#include <sys/types.h>
+
+typedef enum {
+    RESOURCEMATCH_ERROR,
+    RESOURCEMATCH_MATCH,
+    RESOURCEMATCH_NOMATCH
+} resourcematch_result_t;
+
+typedef struct {
+    char type;
+    char *raw;
+    union {
+        const char *string;
+        long long int lli;
+    } result;
+} resourcematch_group_t;
+
+typedef struct {
+    size_t groups;
+    resourcematch_group_t *group;
+} resourcematch_extract_t;
+
+resourcematch_result_t resourcematch_match(const char *pattern, const char *string, resourcematch_extract_t **extract);
+void resourcematch_extract_free(resourcematch_extract_t *extract);
+
+#endif