core: merge the configfile-searching code, isolinux generic names

Merge the config file searching code between syslinux and isolinux,
and make isolinux also recognize the generic names "syslinux" and
"syslinux.cfg".  Thus, isolinux now searches for configuration files
in the following order:

	/boot/isolinux/isolinux.cfg
	/boot/isolinux/syslinux.cfg
	/isolinux/isolinux.cfg
	/isolinux/syslinux.cfg
	/boot/syslinux/isolinux.cfg
	/boot/syslinux/syslinux.cfg
	/syslinux/isolinux.cfg
	/syslinux/syslinux.cfg
	/isolinux.cfg
	/syslinux.cfg

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

2 files changed, 39 insertions, 42 deletions

diff --git a/core/fs/iso9660/iso9660.c b/core/fs/iso9660/iso9660.c
index d695e439..62137d0d 100644
--- a/core/fs/iso9660/iso9660.c
+++ b/core/fs/iso9660/iso9660.c
@@ -273,30 +273,21 @@ static int iso_readdir(struct file *file, struct dirent *dirent)
 /* Load the config file, return 1 if failed, or 0 */
 static int iso_load_config(void)
 {
-    const char *search_directories[] = {
+    static const char *search_directories[] = {
 	"/boot/isolinux", 
 	"/isolinux",
+	"/boot/syslinux", 
+	"/syslinux", 
 	"/",
 	NULL
     };
-    com32sys_t regs;
-    int i;
-    
-    for (i = 0; search_directories[i]; i++) {
-	    memset(&regs, 0, sizeof regs);
-	    snprintf(ConfigName, FILENAME_MAX, "%s/isolinux.cfg",
-		     search_directories[i]);
-	    regs.edi.w[0] = OFFS_WRT(ConfigName, 0);
-	    call16(core_open, &regs, &regs);
-	    if (!(regs.eflags.l & EFLAGS_ZF))
-		break;
-    }
-    if (!search_directories[i])
-	return -1;
-    
-    /* Set the current working directory */
-    chdir(search_directories[i]);
-    return 0;
+    static const char *filenames[] = {
+	"isolinux.cfg",
+	"syslinux.cfg",
+	NULL
+    };
+
+    return search_config(search_directories, filenames);
 }
 
 static int iso_fs_init(struct fs_info *fs)
diff --git a/core/fs/lib/loadconfig.c b/core/fs/lib/loadconfig.c
index db538b87..c2fd9721 100644
--- a/core/fs/lib/loadconfig.c
+++ b/core/fs/lib/loadconfig.c
@@ -4,6 +4,34 @@
 #include <core.h>
 #include <fs.h>
 
+int search_config(const char *search_directories[], const char *filenames[])
+{
+    char confignamebuf[FILENAME_MAX];
+    com32sys_t regs;
+    const char *sd, **sdp;
+    const char *sf, **sfp;
+
+    for (sdp = search_directories; (sd = *sdp); sdp++) {
+	for (sfp = filenames; (sf = *sfp); sfp++) {
+	    memset(&regs, 0, sizeof regs);
+	    snprintf(confignamebuf, sizeof confignamebuf,
+		     "%s%s%s",
+		     sd, (*sd && sd[strlen(sd)-1] == '/') ? "" : "/",
+		     sf);
+	    realpath(ConfigName, confignamebuf, FILENAME_MAX);
+	    regs.edi.w[0] = OFFS_WRT(ConfigName, 0);
+	    dprintf("Config search: %s\n", ConfigName);
+	    call16(core_open, &regs, &regs);
+	    if (!(regs.eflags.l & EFLAGS_ZF)) {
+		chdir(sd);
+		return 0;	/* Got it */
+	    }
+	}
+    }
+
+    return -1;
+}
+
 /*
  * Standard version of load_config for extlinux/syslinux filesystems.
  *
@@ -13,7 +41,6 @@
  */
 int generic_load_config(void)
 {
-    char confignamebuf[FILENAME_MAX];
     static const char *search_directories[] = {
 	NULL,			/* CurrentDirName */
 	"/boot/syslinux", 
@@ -26,31 +53,10 @@ int generic_load_config(void)
 	"syslinux.cfg",
 	NULL
     };
-    com32sys_t regs;
-    int i, j;
 
     search_directories[0] = CurrentDirName;
 
     dprintf("CurrentDirName: \"%s\"\n", CurrentDirName);
 
-    for (i = *CurrentDirName ? 0 : 1; search_directories[i]; i++) {
-	const char *sd = search_directories[i];
-	for (j = 0; filenames[j]; j++) {
-	    memset(&regs, 0, sizeof regs);
-	    snprintf(confignamebuf, sizeof confignamebuf,
-		     "%s%s%s",
-		     sd, (*sd && sd[strlen(sd)-1] == '/') ? "" : "/",
-		     filenames[j]);
-	    realpath(ConfigName, confignamebuf, FILENAME_MAX);
-	    regs.edi.w[0] = OFFS_WRT(ConfigName, 0);
-	    dprintf("Config search: %s\n", ConfigName);
-	    call16(core_open, &regs, &regs);
-	    if (!(regs.eflags.l & EFLAGS_ZF)) {
-		chdir(search_directories[i]);
-		return 0;	/* Got it */
-	    }
-	}
-    }
-
-    return -1;
+    return search_config(search_directories, filenames);
 }