X-Git-Url: http://mj.ucw.cz/gitweb/?a=blobdiff_plain;f=lib%2Fparams.c;h=ac756ad79a313661e13f3d67cf85ec5e3cd43bf6;hb=93c1c6bcc9e2b52652b859986354ddd54ef34058;hp=0e6edbb03f85c4e3034c57a1bf0a0a40d776554e;hpb=d6dcc545806168d496ecc52ca52603fdc0dfd395;p=pciutils.git

diff --git a/lib/params.c b/lib/params.c
index 0e6edbb..ac756ad 100644
--- a/lib/params.c
+++ b/lib/params.c
@@ -1,9 +1,11 @@
 /*
  *	The PCI Library -- Parameters
  *
- *	Copyright (c) 2008 Martin Mares <mj@ucw.cz>
+ *	Copyright (c) 2008--2023 Martin Mares <mj@ucw.cz>
  *
- *	Can be freely distributed and used under the terms of the GNU GPL.
+ *	Can be freely distributed and used under the terms of the GNU GPL v2+.
+ *
+ *	SPDX-License-Identifier: GPL-2.0-or-later
  */
 
 #include <stdio.h>
@@ -26,10 +28,24 @@ pci_get_param(struct pci_access *acc, char *param)
 void
 pci_define_param(struct pci_access *acc, char *param, char *value, char *help)
 {
-  struct pci_param *p = pci_malloc(acc, sizeof(*p));
+  struct pci_param *p, **pp;
 
-  p->next = acc->params;
-  acc->params = p;
+  for (pp=&acc->params; p = *pp; pp=&p->next)
+    {
+      int cmp = strcmp(p->param, param);
+      if (!cmp)
+	{
+	  if (strcmp(p->value, value) || strcmp(p->help, help))
+	    acc->error("Parameter %s re-defined differently", param);
+	  return;
+	}
+      if (cmp > 0)
+	break;
+    }
+
+  p = pci_malloc(acc, sizeof(*p));
+  p->next = *pp;
+  *pp = p;
   p->param = param;
   p->value = value;
   p->value_malloced = 0;
@@ -85,4 +101,3 @@ pci_walk_params(struct pci_access *acc, struct pci_param *prev)
   else
     return prev->next;
 }
-