Avoid unnecessary recompilation of lex files.

[gedcom-parse.git] / gedcom / encoding.c

diff --git a/gedcom/encoding.c b/gedcom/encoding.c
index 23e65bdf3324cab0badaa554d85178a540e2cfb9..d97f63c99aec7a971be936f73b92dd45125d4003 100644 (file)
--- a/gedcom/encoding.c
+++ b/gedcom/encoding.c
@@ -99,6 +99,54 @@ void cleanup_encodings()
   hash_free(encodings);
 }
 
+/* Let function be called before main() */
+void update_gconv_search_path() __attribute__ ((constructor));
+
+/* Note:
+
+   The environment variable GCONV_PATH has to be adjusted before the very
+   first call of iconv_open.  For the most general case, it means that we
+   have to make our own constructor here (in case some of the other library
+   constructors would use iconv_open).
+
+   However, it looks like a change of an environment variable in a constructor
+   doesn't always survive until the main() function.  This is the case if
+   the environment variable is a new one, for which there was no room yet
+   in the initial environment.  The initial environment is located on the
+   stack, but when variables are added, it is moved to the heap (to be able
+   to grow).  Now, the main function takes again the one from the stack, not
+   from the heap, so changes are lost.
+
+   For this, the function below will also be called in gedcom_init(), which
+   needs to be called as early as possible in the program.
+ */
+
+void update_gconv_search_path()
+{
+  char *gconv_path;
+  /* Add gedcom data directory to gconv search path */
+  gconv_path = getenv(GCONV_SEARCH_PATH);
+  if (gconv_path == NULL || strstr(gconv_path, PKGDATADIR) == NULL) {
+    char *new_gconv_path;
+    if (gconv_path == NULL) {
+      new_gconv_path = (char *)malloc(strlen(GCONV_SEARCH_PATH)
+                                     + strlen(PKGDATADIR)
+                                     + 2);
+      sprintf(new_gconv_path, "%s=%s", GCONV_SEARCH_PATH, PKGDATADIR);
+    }
+    else {
+      new_gconv_path = (char *)malloc(strlen(GCONV_SEARCH_PATH)
+                                     + strlen(gconv_path)
+                                     + strlen(PKGDATADIR)
+                                     + 3);
+      sprintf(new_gconv_path, "%s=%s:%s",
+             GCONV_SEARCH_PATH, gconv_path, PKGDATADIR);
+    }
+    /* Ignore failures of putenv (can't do anything about it anyway) */
+    putenv(new_gconv_path);
+  }
+}
+
 void init_encodings()
 {
   if (encodings == NULL) {
@@ -107,33 +155,9 @@ void init_encodings()
     char gedcom_n[MAXBUF + 1];
     char charwidth[MAXBUF + 1];
     char iconv_n[MAXBUF + 1];
-    char *gconv_path;
 
     atexit(cleanup_encodings);
     
-    /* Add gedcom data directory to gconv search path */
-    gconv_path = getenv(GCONV_SEARCH_PATH);
-    if (gconv_path == NULL || strstr(gconv_path, PKGDATADIR) == NULL) {
-      char *new_gconv_path;
-      if (gconv_path == NULL) {
-       new_gconv_path = (char *)malloc(strlen(GCONV_SEARCH_PATH)
-                                       + strlen(PKGDATADIR)
-                                       + 2);
-       sprintf(new_gconv_path, "%s=%s", GCONV_SEARCH_PATH, PKGDATADIR);
-      }
-      else {
-       new_gconv_path = (char *)malloc(strlen(GCONV_SEARCH_PATH)
-                                       + strlen(gconv_path)
-                                       + strlen(PKGDATADIR)
-                                       + 3);
-       sprintf(new_gconv_path, "%s=%s:%s",
-               GCONV_SEARCH_PATH, gconv_path, PKGDATADIR);
-      }
-      if (putenv(new_gconv_path) != 0) {
-       gedcom_warning(_("Failed updating conversion module path"));
-      }
-    }
-
     encodings = hash_create(HASHCOUNT_T_MAX, NULL, NULL);
     hash_set_allocator(encodings, node_alloc, node_free, NULL);