# HG changeset patch
# User Mike Becker <universe@uap-core.de>
# Date 1586073998 -7200
# Node ID 764e9fac530dd1c4b686e578cf03c5851e065cc9
# Parent  5c2e4da00b0454a0eb14be73a2b44c615d74614c
look up temp location + coherent return codes

diff -r 5c2e4da00b04 -r 764e9fac530d dav/main.c
--- a/dav/main.c	Sun Apr 05 09:34:58 2020 +0200
+++ b/dav/main.c	Sun Apr 05 10:06:38 2020 +0200
@@ -1225,10 +1225,43 @@
         }
     }
     
-    // open temporary file
-    // TODO: look up the location of the temp directory, maybe add sys_* funcs
-    char outfile[24];
-    strncpy(outfile, ".dav-edit-XXXXXX", 24);
+    // get temp dir
+    char* envtmp = getenv("TMPDIR");
+    char* outfile;
+    if(envtmp) {
+        size_t len = strlen(envtmp);
+        outfile = malloc(len+24);
+        memcpy(outfile, envtmp, len+1);
+        if(outfile[len-1] != '/') {
+            outfile[len] = '/';
+            outfile[len+1] = 0;
+        }
+    } else {
+        outfile = malloc(24);
+        strncpy(outfile, "/tmp/", 24);
+    }
+    
+    // check temp dir and fall back to $HOME
+    if(access(outfile, W_OK)) {
+        char* home = getenv("HOME");
+        if(home) {
+            size_t len = strlen(envtmp);
+            outfile = malloc(len+24);
+            memcpy(outfile, home, len+1);
+            if(outfile[len-1] != '/') {
+                outfile[len] = '/';
+                outfile[len+1] = 0;
+            }
+        } else {
+            // fallback did not work, report last error from access()
+            perror("Cannot write to temporary location");
+            free(outfile);
+            return -1;
+        }
+    }
+    
+    // create temp file and open it
+    outfile = strncat(outfile, ".dav-edit-XXXXXX", 23);
     int tmp_fd = mkstemp(outfile);
     if(tmp_fd < 0) {
         perror("Cannot open temporary file");
@@ -1240,11 +1273,13 @@
         FILE* tmp_stream = sys_fopen(outfile, "wb");
         if(!tmp_stream) {
             perror("Cannot open temporary file");
+            free(outfile);
             close(tmp_fd);
             return -1;
         }
         if(dav_get_content(res, tmp_stream, (dav_write_func)fwrite)) {
             print_resource_error(sn, path);
+            free(outfile);
             close(tmp_fd);
             sys_unlink(outfile);
             return -1;
@@ -1256,6 +1291,7 @@
     SYS_STAT tmp_stat;
     if(sys_stat(outfile, &tmp_stat)) {
         perror("Cannot stat temporary file");
+        free(outfile);
         close(tmp_fd);
         sys_unlink(outfile);
         return -1;
@@ -1272,11 +1308,11 @@
     pid_t pid = fork();
     if(pid < 0) {
         perror("Cannot create process for editor");
-        ret = 1;
+        ret = -1;
     } else if(pid == 0) {
         if(execvp(viargs[0], viargs)) {
             perror("Opening the editor failed");
-            return 1;
+            return -1;
         }
     } else {
         int status = -1;
@@ -1286,29 +1322,29 @@
         } else if(WEXITSTATUS(status)) {
             fprintf(stderr,
                     "Editor closed abnormally - file will not be uploaded.\n");
-            ret = 1;
+            ret = -1;
         } else {
             // check if the file has changed
             if (sys_stat(outfile, &tmp_stat)) {
                 // very rare case when someone concurrently changes permissions
                 perror("Cannot stat temporary file");
-                ret = 1;
+                ret = -1;
             } else if (dl_mtime < tmp_stat.st_mtime) {
                 // upload changed file
                 FILE* tmp_stream = sys_fopen(outfile, "rb");
                 if(!tmp_stream) {
                     perror("Cannot open temporary file");
-                    close(tmp_fd);
-                    return -1;
-                }
-                dav_set_content(res, tmp_stream,
-                        (dav_read_func)fread,
-                        (dav_seek_func)file_seek);
-                dav_set_content_length(res, tmp_stat.st_size);
-                ret = dav_store(res);
-                fclose(tmp_stream);
-                if(ret) {
-                    print_resource_error(sn, path);
+                    ret = -1;
+                } else {
+                    dav_set_content(res, tmp_stream,
+                            (dav_read_func)fread,
+                            (dav_seek_func)file_seek);
+                    dav_set_content_length(res, tmp_stat.st_size);
+                    ret = dav_store(res);
+                    fclose(tmp_stream);
+                    if(ret) {
+                        print_resource_error(sn, path);
+                    }
                 }
             } else {
                 printf("No changes by user - file will not be uploaded.\n");
@@ -1323,6 +1359,7 @@
     } else {
         sys_unlink(outfile);
     }
+    free(outfile);
     free(path);
     
     return ret;