directory write ability check for some piler binaries

src/config.h

@@ -14,7 +14,7 @@
 
 #define VERSION "1.1.1-pre"
 
-#define BUILD 889
+#define BUILD 890
 
 #define HOSTID "mailarchiver"
 

src/misc.c

@@ -560,6 +560,24 @@ void *get_in_addr(struct sockaddr *sa){
 }
 
 
+int can_i_write_current_directory(){
+   int fd;
+   char filename[SMALLBUFSIZE];
+
+   snprintf(filename, sizeof(filename)-1, "__piler_%d", getpid());
+
+   fd = open(filename, O_CREAT|O_RDWR, S_IRUSR|S_IWUSR|S_IRGRP);
+   if(fd == -1){
+      return 0;
+   }
+
+   close(fd);
+   unlink(filename);
+
+   return 1;
+}
+
+
 #ifndef _GNU_SOURCE
 char *strcasestr(const char *s, const char *find){
    char c, sc;

src/misc.h

@@ -42,6 +42,8 @@ void strtolower(char *s);
 
 void *get_in_addr(struct sockaddr *sa);
 
+int can_i_write_current_directory();
+
 #ifndef _GNU_SOURCE
    char *strcasestr(const char *s, const char *find);
 #endif

src/pilerexport.c

@@ -351,6 +351,8 @@ int main(int argc, char **argv){
 
    regfree(&regexp);
 
+   if(!can_i_write_current_directory()) __fatal("cannot write current directory!");
+
    (void) openlog("pilerexport", LOG_PID, LOG_MAIL);
 
    if(exportall == 1){

src/pilerimport.c

@@ -647,6 +647,8 @@ int main(int argc, char **argv){
 
    if(!mbox[0] && !mboxdir && !emlfile && !directory && !imapserver && !pop3server && import_from_gui == 0) usage();
 
+   if(!can_i_write_current_directory()) __fatal("cannot write current directory!");
+
    cfg = read_config(configfile);
 
    /* make sure we don't discard messages without a valid Message-Id when importing manually */

src/reindex.c

@@ -205,6 +205,7 @@ int main(int argc, char **argv){
 
    if(all == 0 && (from_id <= 0 || to_id <= 0) ) usage();
 
+   if(!can_i_write_current_directory()) __fatal("cannot write current directory!");
 
    (void) openlog("reindex", LOG_PID, LOG_MAIL);
 

src/test.c

@@ -32,6 +32,8 @@ int main(int argc, char **argv){
       exit(1);
    }
 
+   if(!can_i_write_current_directory()) __fatal("cannot write current directory!");
+
    if(stat(argv[1], &st) != 0){
       fprintf(stderr, "%s is not found\n", argv[1]);
       return 0;