[patch] Proposed patch

IGNORE_UPDOWNSTREAM_SIGPIPE.patch (text/plain), 8.46 KB, created by Luum on 2017-09-27 21:39:58 UTC

foomatic-rip failure status fix

Changes execution of renderer thread in the foomatic-rip package to fail
whenever any of its individual sub-comands fails.

Parent process now ignores SIGPIPE calls from upstream/downstream CUPS filters,
per https://www.cups.org/doc/api-filter.html, while correctly noting child
process failures and exiting accordingly.

NOTE: Child processes still abort on SIGPIPE. It is now the responsibility
of the parent to note this crash and exit gracefully.

diff -u filter/foomatic-rip/foomaticrip.c filter-new/foomatic-rip/foomaticrip.c
--- filter/foomatic-rip/foomaticrip.c	2015-10-20 07:59:20.000000000 -0700
+++ filter-new/foomatic-rip/foomaticrip.c	2017-09-26 10:37:23.747220621 -0700
@@ -517,7 +517,7 @@
     while (isspace(*p++) && left-- > 0)
         ;
 
-    fwrite((void *)p, left, 1, postpipe);
+    fwrite_or_die((void *)p, left, 1, postpipe);
     fflush(postpipe);
 }
 
@@ -572,7 +572,7 @@
         }
     }
 
-    n = fread(buf, 1, sizeof(buf) - 1, file);
+    n = fread_or_die(buf, 1, sizeof(buf) - 1, file);
     buf[n] = '\0';
     type = guess_file_type(buf, n, &startpos);
     /* We do not use any JCL preceeded to the inputr data, as it is simply
@@ -745,6 +745,7 @@
 
     signal(SIGTERM, signal_terminate);
     signal(SIGINT, signal_terminate);
+    signal(SIGPIPE, SIG_IGN);
 
 
     config_from_file(CONFIG_PATH "/filter.conf");
diff -u filter/foomatic-rip/pdf.c filter-new/foomatic-rip/pdf.c
--- filter/foomatic-rip/pdf.c	2015-10-09 18:32:52.000000000 -0700
+++ filter-new/foomatic-rip/pdf.c	2017-09-26 10:37:23.751220608 -0700
@@ -56,7 +56,7 @@
     if (!pd)
       rip_die(EXIT_STARVED, "Failed to execute ghostscript to determine number of input pages!\n");
 
-    bytes = fread(output, 1, 31, pd);
+    bytes = fread_or_die(output, 1, 31, pd);
     pclose(pd);
 
     if (bytes <= 0 || sscanf(output, "PageCount: %d", &pagecount) < 1)
diff -u filter/foomatic-rip/postscript.c filter-new/foomatic-rip/postscript.c
--- filter/foomatic-rip/postscript.c	2015-07-04 04:21:47.000000000 -0700
+++ filter-new/foomatic-rip/postscript.c	2017-09-26 10:36:29.279398863 -0700
@@ -1032,14 +1032,14 @@
 
                     if (!isempty(psfifo->data)) {
                         /* Send psfifo to renderer */
-                        fwrite(psfifo->data, psfifo->len, 1, rendererhandle);
+                        fwrite_or_die(psfifo->data, psfifo->len, 1, rendererhandle);
                         /* flush psfifo */
                         dstrclear(psfifo);
                     }
 
                     /* Send line to renderer */
                     if (!printprevpage) {
-                        fwrite(line->data, line->len, 1, rendererhandle);
+                        fwrite_or_die(line->data, line->len, 1, rendererhandle);
 
                         while (stream_next_line(line, stream) > 0) {
                             if (startswith(line->data, "%%")) {
@@ -1049,7 +1049,7 @@
                                 break;
                             }
                             else {
-                                fwrite(line->data, line->len, 1, rendererhandle);
+                                fwrite_or_die(line->data, line->len, 1, rendererhandle);
                                 linect++;
                             }
                         }
@@ -1141,14 +1141,14 @@
 
         if (psfifo->len) {
             /* Send psfifo to the renderer */
-            fwrite(psfifo->data, psfifo->len, 1, rendererhandle);
+            fwrite_or_die(psfifo->data, psfifo->len, 1, rendererhandle);
             dstrclear(psfifo);
         }
 
         /* Print the rest of the input data */
         if (more_stuff) {
             while (stream_next_line(tmp, stream))
-                fwrite(tmp->data, tmp->len, 1, rendererhandle);
+                fwrite_or_die(tmp->data, tmp->len, 1, rendererhandle);
         }
     }
 
@@ -1197,7 +1197,7 @@
 
     /* Feed the PostScript header and the FIFO contents */
     if (prepend)
-        fwrite(prepend->data, prepend->len, 1, kid3in);
+        fwrite_or_die(prepend->data, prepend->len, 1, kid3in);
 
     /* We are the parent, return glob to the file handle */
     *fd = kid3in;
diff -u filter/foomatic-rip/process.c filter-new/foomatic-rip/process.c
--- filter/foomatic-rip/process.c	2015-07-04 04:21:47.000000000 -0700
+++ filter-new/foomatic-rip/process.c	2017-09-25 12:54:46.279584580 -0700
@@ -125,6 +125,10 @@
     }
 
     if (pid == 0) { /* Child */
+
+        // Reset sigpipe behavior to default for all children
+        signal(SIGPIPE, SIG_DFL);
+
         if (pipe_in) {
             close(pfdin[1]);
             in = fdopen(pfdin[0], "r");
@@ -179,7 +183,7 @@
     if (out && dup2(fileno(out), fileno(stdout)) < 0)
         rip_die(EXIT_PRNERR_NORETRY_BAD_SETTINGS, "%s: Could not dup stdout\n", (const char *)cmd);
 
-    execl(get_modern_shell(), get_modern_shell(), "-c", (const char *)cmd, (char *)NULL);
+    execl(get_modern_shell(), get_modern_shell(), "-e", "-c", (const char *)cmd, (char *)NULL);
 
     _log("Error: Executing \"%s -c %s\" failed (%s).\n", get_modern_shell(), (const char *)cmd, strerror(errno));
     return EXIT_PRNERR_NORETRY_BAD_SETTINGS;
diff -u filter/foomatic-rip/renderer.c filter-new/foomatic-rip/renderer.c
--- filter/foomatic-rip/renderer.c	2015-07-04 04:21:47.000000000 -0700
+++ filter-new/foomatic-rip/renderer.c	2017-09-26 10:37:23.751220608 -0700
@@ -52,7 +52,7 @@
         return 0;
     }
 
-    bytes = fread(output, 1, 10, pd);
+    bytes = fread_or_die(output, 1, 10, pd);
     pclose(pd);
 
     if (bytes > 0 && startswith(output, "hello"))
@@ -288,7 +288,7 @@
          * also contains the "<esc>%-12345X" which has to be in the beginning
          * of the job */
         if (p)
-            fwrite(original_opts[0], 1, p - original_opts[0], stream);
+            fwrite_or_die(original_opts[0], 1, p - original_opts[0], stream);
         else
             fprintf(stream, "%s\n", original_opts[0]);
 
@@ -392,7 +392,7 @@
 
     /* A JCL trailer */
     if (argv_count(jclprepend) > 0 && !driverjcl)
-        fwrite(jclappend->data, jclappend->len, 1, fileh);
+        fwrite_or_die(jclappend->data, jclappend->len, 1, fileh);
 
     fclose(in);
     if (fclose(fileh) != 0)
diff -u filter/foomatic-rip/util.c filter-new/foomatic-rip/util.c
--- filter/foomatic-rip/util.c	2015-12-12 15:21:05.000000000 -0800
+++ filter-new/foomatic-rip/util.c	2017-09-26 10:37:23.759220582 -0700
@@ -29,6 +29,7 @@
 #include <unistd.h>
 #include <stdarg.h>
 #include <assert.h>
+#include <errno.h>
 
 
 const char* shellescapes = "|;<>&!$\'\"`#*?()[]{}";
@@ -291,6 +292,22 @@
     return psrc +1;
 }
 
+size_t fwrite_or_die(const void* ptr, size_t size, size_t count, FILE* stream) {
+  size_t res = fwrite(ptr, size, count, stream);
+  if (ferror(stream))
+    rip_die(EXIT_PRNERR, "Encountered error %s during fwrite", strerror(errno));
+
+  return res;
+}
+
+size_t fread_or_die(void* ptr, size_t size, size_t count, FILE* stream) {
+  size_t res = fread(ptr, size, count, stream);
+  if (ferror(stream))
+    rip_die(EXIT_PRNERR, "Encountered error %s during fread", strerror(errno));
+
+  return res;
+}
+
 int find_in_path(const char *progname, const char *paths, char *found_in)
 {
     char *pathscopy;
@@ -1111,15 +1128,15 @@
 
     if (alreadyread && alreadyread_len)
     {
-        if (fwrite(alreadyread, 1, alreadyread_len, dest) < alreadyread_len)
+        if (fwrite_or_die(alreadyread, 1, alreadyread_len, dest) < alreadyread_len)
         {
             _log("Could not write to temp file\n");
             return 0;
         }
     }
 
-    while ((bytes = fread(buf, 1, 8192, src)))
-        fwrite(buf, 1, bytes, dest);
+    while ((bytes = fread_or_die(buf, 1, 8192, src)))
+        fwrite_or_die(buf, 1, bytes, dest);
 
     return !ferror(src) && !ferror(dest);
 }
diff -u filter/foomatic-rip/util.h filter-new/foomatic-rip/util.h
--- filter/foomatic-rip/util.h	2015-06-26 08:45:26.000000000 -0700
+++ filter-new/foomatic-rip/util.h	2017-09-26 10:38:16.443048131 -0700
@@ -98,6 +98,11 @@
 */
 const char * strncpy_tochar(char *dest, const char *src, size_t max, const char *stopchars);
 
+/* "safe" versions of standard <cstdio> fwrite and fread that will cause the
+ * program to exit gracefully when a write/read fails */
+size_t fwrite_or_die(const void* ptr, size_t size, size_t count, FILE* stream);
+size_t fread_or_die(void* ptr, size_t size, size_t count, FILE* stream);
+
 /* 'paths' is a colon seperated list of paths (like $PATH) 
  * 'found_in' may be NULL if it is not needed */
 int find_in_path(const char *progname, const char *paths, char *found_in);