+/* Try to open a configuration file. If "env" is specified, open the
+ * value of the specified environment variable. Otherwise look for a
+ * file "local" in the home directory or a file "global" in global
+ * file system. If "result" is non-NULL, a pointer to a newly
+ * allocated buffer containing the used configuration file is
+ * stored there.*/
+FILE *pa_open_config_file(const char *global, const char *local, const char *env, char **result) {
+ const char *e;
+ char h[PATH_MAX];
+
+ if (env && (e = getenv(env))) {
+ if (result)
+ *result = pa_xstrdup(e);
+ return fopen(e, "r");
+ }
+
+ if (local && pa_get_home_dir(h, sizeof(h))) {
+ FILE *f;
+ char *l;
+
+ l = pa_sprintf_malloc("%s/%s", h, local);
+ f = fopen(l, "r");
+
+ if (f || errno != ENOENT) {
+ if (result)
+ *result = l;
+ else
+ pa_xfree(l);
+ return f;
+ }
+
+ pa_xfree(l);
+ }
+
+ if (!global) {
+ if (result)
+ *result = NULL;
+ errno = ENOENT;
+ return NULL;
+ }
+
+ if (result)
+ *result = pa_xstrdup(global);
+
+ return fopen(global, "r");
+}
+
+/* Format the specified data as a hexademical string */
+char *pa_hexstr(const uint8_t* d, size_t dlength, char *s, size_t slength) {
+ size_t i = 0, j = 0;
+ const char hex[] = "0123456789abcdef";
+ assert(d && s && slength > 0);
+
+ while (i < dlength && j+3 <= slength) {
+ s[j++] = hex[*d >> 4];
+ s[j++] = hex[*d & 0xF];
+
+ d++;
+ i++;
+ }
+
+ s[j < slength ? j : slength] = 0;
+ return s;
+}
+
+/* Convert a hexadecimal digit to a number or -1 if invalid */
+static int hexc(char c) {
+ if (c >= '0' && c <= '9')
+ return c - '0';
+
+ if (c >= 'A' && c <= 'F')
+ return c - 'A' + 10;
+
+ if (c >= 'a' && c <= 'f')
+ return c - 'a' + 10;
+
+ return -1;
+}
+
+/* Parse a hexadecimal string as created by pa_hexstr() to a BLOB */
+size_t pa_parsehex(const char *p, uint8_t *d, size_t dlength) {
+ size_t j = 0;
+ assert(p && d);
+
+ while (j < dlength && *p) {
+ int b;
+
+ if ((b = hexc(*(p++))) < 0)
+ return (size_t) -1;
+
+ d[j] = (uint8_t) (b << 4);
+
+ if (!*p)
+ return (size_t) -1;
+
+ if ((b = hexc(*(p++))) < 0)
+ return (size_t) -1;
+
+ d[j] |= (uint8_t) b;
+ j++;
+ }
+
+ return j;
+}
+
+/* Return the fully qualified domain name in *s */
+char *pa_get_fqdn(char *s, size_t l) {
+ char hn[256];
+ struct addrinfo *a, hints;
+
+ if (!pa_get_host_name(hn, sizeof(hn)))
+ return NULL;
+
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = AF_UNSPEC;
+ hints.ai_flags = AI_CANONNAME;
+
+ if (getaddrinfo(hn, NULL, &hints, &a) < 0 || !a || !a->ai_canonname || !*a->ai_canonname)
+ return pa_strlcpy(s, hn, l);
+
+ pa_strlcpy(s, a->ai_canonname, l);
+ freeaddrinfo(a);
+ return s;
+}
+
+/* Returns nonzero when *s starts with *pfx */
+int pa_startswith(const char *s, const char *pfx) {
+ size_t l;
+ assert(s && pfx);
+ l = strlen(pfx);
+
+ return strlen(s) >= l && strncmp(s, pfx, l) == 0;
+}
+
+/* if fn is null return the polypaudio run time path in s (/tmp/polypaudio)
+ * if fn is non-null and starts with / return fn in s
+ * otherwise append fn to the run time path and return it in s */
+char *pa_runtime_path(const char *fn, char *s, size_t l) {
+ char u[256];
+
+ if (fn && *fn == '/')
+ return pa_strlcpy(s, fn, l);
+
+ snprintf(s, l, PA_RUNTIME_PATH_PREFIX"%s%s%s", pa_get_user_name(u, sizeof(u)), fn ? "/" : "", fn ? fn : "");
+ return s;
+}