Fix warnings about unused return values. This includes some code changes

to do a better job of error checking.

14 files changed, 113 insertions, 47 deletions

diff --git a/src/clinet.c b/src/clinet.c
index 4e4767e..010a884 100644
--- a/src/clinet.c
+++ b/src/clinet.c
@@ -92,6 +92,7 @@ int dcc_connect_by_addr(struct sockaddr *sa, size_t salen,
     int tries = 3;
 
     dcc_sockaddr_to_string(sa, salen, &s);
+    if (s == NULL) return EXIT_OUT_OF_MEMORY;
 
     rs_trace("started connecting to %s", s);
 
diff --git a/src/dotd.c b/src/dotd.c
index b98f03d..b09b336 100644
--- a/src/dotd.c
+++ b/src/dotd.c
@@ -272,9 +272,9 @@ int dcc_get_dotd_info(char **argv, char **dotd_fname,
         }
         else { /* There is no extension (or name ends with a "."). */
           if (tmp_dotd_fname[strlen(tmp_dotd_fname) - 1] == '.')
-            asprintf(dotd_fname, "%s%s", tmp_dotd_fname, "d");
+            checked_asprintf(dotd_fname, "%s%s", tmp_dotd_fname, "d");
           else
-            asprintf(dotd_fname, "%s%s", tmp_dotd_fname, ".d");
+            checked_asprintf(dotd_fname, "%s%s", tmp_dotd_fname, ".d");
           if (*dotd_fname == NULL) {
             return EXIT_OUT_OF_MEMORY;
           }
diff --git a/src/emaillog.c b/src/emaillog.c
index 9e68a0b..e106529 100644
--- a/src/emaillog.c
+++ b/src/emaillog.c
@@ -35,6 +35,7 @@
 #include "trace.h"
 #include "bulk.h"
 #include "snprintf.h"
+#include "exitcode.h"
 
 /* if never_send_email is true, we won't send email
    even if should_send_email is true */
@@ -84,21 +85,33 @@ int dcc_add_file_to_log_email(const char *description,
   char end[] = "\nEND ";
   int in_fd = 0;
   off_t fsize;
+  int ret;
 
   if (never_send_email) return 0;
 
-  if (dcc_open_read(fname, &in_fd, &fsize))
-      return 1;
+  ret = dcc_open_read(fname, &in_fd, &fsize);
+  if (ret != 0) return ret;
 
-  write(email_fileno, begin, strlen(begin));
-  write(email_fileno, description, strlen(description));
-  write(email_fileno, "\n", 1);
+  ret = write(email_fileno, begin, strlen(begin));
+  if (ret != (ssize_t) strlen(begin)) return EXIT_IO_ERROR;
 
-  dcc_pump_readwrite(email_fileno, in_fd, fsize);
+  ret = write(email_fileno, description, strlen(description));
+  if (ret != (ssize_t) strlen(description)) return EXIT_IO_ERROR;
 
-  write(email_fileno, end, strlen(end));
-  write(email_fileno, description, strlen(description));
-  write(email_fileno, "\n", 1);
+  ret = write(email_fileno, "\n", 1);
+  if (ret != 1) return EXIT_IO_ERROR;
+
+  ret = dcc_pump_readwrite(email_fileno, in_fd, fsize);
+  if (ret != 0) return ret;
+
+  ret = write(email_fileno, end, strlen(end));
+  if (ret != (ssize_t) strlen(end)) return EXIT_IO_ERROR;
+
+  ret = write(email_fileno, description, strlen(description));
+  if (ret != (ssize_t) strlen(description)) return EXIT_IO_ERROR;
+
+  ret = write(email_fileno, "\n", 1);
+  if (ret != 1) return EXIT_IO_ERROR;
 
   close(in_fd);
 
@@ -113,12 +126,17 @@ void dcc_maybe_send_email(void) {
     whom_to_blame = dcc_emaillog_whom_to_blame;
   }
   char *cant_send_message_to;
+  int ret;
 
   if (should_send_email == 0) return;
   if (never_send_email) return;
 
   rs_log_warning(will_send_message_format, whom_to_blame);
-  asprintf(&cant_send_message_to, cant_send_message_format, whom_to_blame);
+  ret = asprintf(&cant_send_message_to, cant_send_message_format, whom_to_blame);
+  if (ret == -1) {
+      fprintf(stderr, "error sending email: asprintf() failed");
+      return;
+  }
 
   if (email_fileno < 0) {
       errno = email_errno;
diff --git a/src/hosts.c b/src/hosts.c
index 5fa1395..aaf4fd9 100644
--- a/src/hosts.c
+++ b/src/hosts.c
@@ -172,8 +172,8 @@ int dcc_get_hostlist(struct dcc_hostdef **ret_list,
     if ((ret = dcc_get_top_dir(&top)) == 0) {
         /* if we failed to get it, just warn */
 
-        asprintf(&path, "%s/hosts", top);
-        if (access(path, R_OK) == 0) {
+        checked_asprintf(&path, "%s/hosts", top);
+        if (path != NULL && access(path, R_OK) == 0) {
             ret = dcc_parse_hosts_file(path, ret_list, ret_nhosts);
             free(path);
             return ret;
@@ -183,8 +183,8 @@ int dcc_get_hostlist(struct dcc_hostdef **ret_list,
         }
     }
 
-    asprintf(&path, "%s/distcc/hosts", SYSCONFDIR);
-    if (access(path, R_OK) == 0) {
+    checked_asprintf(&path, "%s/distcc/hosts", SYSCONFDIR);
+    if (path != NULL && access(path, R_OK) == 0) {
         ret = dcc_parse_hosts_file(path, ret_list, ret_nhosts);
         free(path);
         return ret;
diff --git a/src/mon.c b/src/mon.c
index 7f426d2..7ec2382 100644
--- a/src/mon.c
+++ b/src/mon.c
@@ -259,7 +259,10 @@ static int dcc_mon_do_file(char *dirname, char *filename,
         return 0;
     }
 
-    asprintf(&fullpath, "%s/%s", dirname, filename);
+    checked_asprintf(&fullpath, "%s/%s", dirname, filename);
+    if (fullpath == NULL) {
+      return EXIT_OUT_OF_MEMORY;
+    }
     rs_trace("process %s", fullpath);
 
     /* Remember that the file might disappear at any time, so open it
diff --git a/src/netutil.c b/src/netutil.c
index 7324750..4a7b452 100644
--- a/src/netutil.c
+++ b/src/netutil.c
@@ -177,13 +177,13 @@ int dcc_sockaddr_to_string(struct sockaddr *sa,
             return 0;               /* it's still a valid string */
         }
 
-        asprintf(p_buf, "%s:%s", host, port);
+        checked_asprintf(p_buf, "%s:%s", host, port);
     } else if (sa->sa_family == AF_UNIX) {
         /* NB: The word 'sun' is predefined on Solaris */
         struct sockaddr_un *sa_un = (struct sockaddr_un *) sa;
-        asprintf(p_buf, "UNIX-DOMAIN %s", sa_un->sun_path);
+        checked_asprintf(p_buf, "UNIX-DOMAIN %s", sa_un->sun_path);
     } else {
-        asprintf(p_buf, "UNKNOWN-FAMILY %d", sa->sa_family);
+        checked_asprintf(p_buf, "UNKNOWN-FAMILY %d", sa->sa_family);
     }
 
     return 0;
@@ -200,14 +200,14 @@ int dcc_sockaddr_to_string(struct sockaddr *sa,
         /* The double-cast here suppresses warnings from -Wcast-align. */
         struct sockaddr_in *sain = (struct sockaddr_in *) (void *) sa;
 
-        asprintf(p_buf, "%s:%d", inet_ntoa(sain->sin_addr),
+        checked_asprintf(p_buf, "%s:%d", inet_ntoa(sain->sin_addr),
                  ntohs(sain->sin_port));
     } else if (sa->sa_family == AF_UNIX) {
         /* NB: The word 'sun' is predefined on Solaris */
         struct sockaddr_un *sa_un = (struct sockaddr_un *) sa;
-        asprintf(p_buf, "UNIX-DOMAIN %s", sa_un->sun_path);
+        checked_asprintf(p_buf, "UNIX-DOMAIN %s", sa_un->sun_path);
     } else {
-        asprintf(p_buf, "UNKNOWN-FAMILY %d", sa->sa_family);
+        checked_asprintf(p_buf, "UNKNOWN-FAMILY %d", sa->sa_family);
     }
 
     return 0;
diff --git a/src/serve.c b/src/serve.c
index e6c2232..6ee6dd0 100644
--- a/src/serve.c
+++ b/src/serve.c
@@ -431,7 +431,7 @@ static int tweak_include_arguments_for_server(char **argv,
                 if (argv[i] != NULL) {  /* in case of a dangling -I */
                     if (argv[i][index_of_first_filename_char] == '/') {
                         char *buf;
-                        asprintf(&buf, "%s%s%s",
+                        checked_asprintf(&buf, "%s%s%s",
                                  include_option,
                                  root_dir,
                                  argv[i] + index_of_first_filename_char);
@@ -544,7 +544,7 @@ static int make_temp_dir_and_chdir_for_cpp(int in_fd,
         if ((ret = dcc_r_cwd(in_fd, client_side_cwd)))
             return ret;
 
-        asprintf(server_side_cwd, "%s%s", *temp_dir, *client_side_cwd);
+        checked_asprintf(server_side_cwd, "%s%s", *temp_dir, *client_side_cwd);
         if (*server_side_cwd == NULL) {
             ret = EXIT_OUT_OF_MEMORY;
         } else if ((ret = dcc_mk_tmp_ancestor_dirs(*server_side_cwd))) {
@@ -784,8 +784,10 @@ out_cleanup:
         dcc_stats_event(job_result);
     }
 
-    asprintf(&time_str, " exit:%d sig:%d core:%d ret:%d time:%dms ", WEXITSTATUS(status), WTERMSIG(status), WCOREDUMP(status), ret, time_ms);
-    dcc_job_summary_append(time_str);
+    checked_asprintf(&time_str, " exit:%d sig:%d core:%d ret:%d time:%dms ",
+                     WEXITSTATUS(status), WTERMSIG(status), WCOREDUMP(status),
+                     ret, time_ms);
+    if (time_str != NULL) dcc_job_summary_append(time_str);
     free(time_str);
 
     /* append compiler and input file info */
diff --git a/src/snprintf.c b/src/snprintf.c
index da57960..3ccafbe 100644
--- a/src/snprintf.c
+++ b/src/snprintf.c
@@ -125,17 +125,16 @@
 #include <stdlib.h>
 #endif
 
-#if defined(HAVE_SNPRINTF) && defined(HAVE_VSNPRINTF) && defined(HAVE_C99_VSNPRINTF) \
- && defined(HAVE_VASPRINTF) && defined(HAVE_ASPRINTF)
-/* This ifdef switches on or off basically the whole contents of the file. */
-/* Make the compiler happy with an empty file */
- void dummy_snprintf(void);
- void dummy_snprintf(void) {}
-#else
-
 #include "snprintf.h"
 #include "va_copy.h"
 
+#if !defined(HAVE_SNPRINTF) || \
+    !defined(HAVE_VSNPRINTF) || \
+    !defined(HAVE_C99_VSNPRINTF) || \
+    !defined(HAVE_VASPRINTF) || \
+    !defined(HAVE_ASPRINTF)
+/* Lots of code to define our own vsnprintf(). */
+
 #ifdef HAVE_LONG_DOUBLE
 #define LDOUBLE long double
 #else
@@ -863,7 +862,6 @@ static void dopr_outch(char *buffer, size_t *currlen, size_t maxlen, char c)
 }
 #endif /* HAVE_VASPRINTF */
 
-
 #ifndef HAVE_ASPRINTF
  int asprintf(char **ptr, const char *format, ...)
 {
@@ -879,6 +877,26 @@ static void dopr_outch(char *buffer, size_t *currlen, size_t maxlen, char c)
 }
 #endif /* HAVE_ASPRINTF */
 
+/* Like asprintf(), but on error it sets *ptr to NULL
+ * rather than returning -1. Unlike asprintf(), it
+ * guarantees to always set *ptr.
+ */
+int checked_asprintf(char **ptr, const char *format, ...)
+{
+    va_list ap;
+    int ret;
+
+    *ptr = NULL;
+    va_start(ap, format);
+    ret = vasprintf(ptr, format, ap);
+    va_end(ap);
+
+    if (ret == -1) {
+      *ptr = NULL;
+    }
+    return ret;
+}
+
 #ifdef TEST_SNPRINTF
 
  int sprintf(char *str,const char *fmt,...);
diff --git a/src/snprintf.h b/src/snprintf.h
index 5c5c9e3..db2a19f 100644
--- a/src/snprintf.h
+++ b/src/snprintf.h
@@ -36,3 +36,5 @@ int asprintf(char **,const char *, ...) PRINTF_ATTRIBUTE(2,3);
 #if !HAVE_DECL_VSNPRINTF
 int vsnprintf(char *, size_t, const char *, va_list);
 #endif
+
+int checked_asprintf(char **, const char *, ...) PRINTF_ATTRIBUTE(2,3);
diff --git a/src/srvnet.c b/src/srvnet.c
index 383a679..c2efbca 100644
--- a/src/srvnet.c
+++ b/src/srvnet.c
@@ -86,6 +86,9 @@ static int dcc_listen_by_addr(int fd,
     setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (char *) &one, sizeof(one));
 
     dcc_sockaddr_to_string(sa, salen, &sa_buf);
+    if (sa_buf == NULL) {
+      return EXIT_OUT_OF_MEMORY;
+    }
 
     /* now we've got a socket - we need to bind it */
     if (bind(fd, sa, salen) == -1) {
diff --git a/src/srvrpc.c b/src/srvrpc.c
index 15f73fa..08e3d7f 100644
--- a/src/srvrpc.c
+++ b/src/srvrpc.c
@@ -87,7 +87,7 @@ int dcc_r_cwd(int ifd, char **cwd)
 static int prepend_dir_to_name(const char *dirname, char **path)
 {
     char *buf;
-    asprintf(&buf, "%s%s", dirname, *path);
+    checked_asprintf(&buf, "%s%s", dirname, *path);
     if (buf == NULL) {
             return EXIT_OUT_OF_MEMORY;
     }
diff --git a/src/stats.c b/src/stats.c
index c2ef762..21aeb65 100644
--- a/src/stats.c
+++ b/src/stats.c
@@ -114,7 +114,7 @@ void dcc_stats_event(enum stats_e e) {
         struct statsdata sd;
         memset(&sd, 0, sizeof(sd));
         sd.type = e;
-        write(dcc_statspipe[1], &sd, sizeof(sd));
+        dcc_writex(dcc_statspipe[1], &sd, sizeof(sd));
     }
 }
 
@@ -135,7 +135,7 @@ void dcc_stats_compile_ok(char *compiler, char *filename, struct timeval start,
         sd.time = time_usec;
         strncpy(sd.filename, filename, MAX_FILENAME_LEN);
         strncpy(sd.compiler, compiler, MAX_FILENAME_LEN);
-        write(dcc_statspipe[1], &sd, sizeof(sd));
+        dcc_writex(dcc_statspipe[1], &sd, sizeof(sd));
     }
 }
 
@@ -363,6 +363,7 @@ static void dcc_service_stats_request(int http_fd) {
     socklen_t cli_len = sizeof(cli_addr);
     double loadavg[3];
     int free_space_mb;
+    ssize_t ret;
 
     const char replytemplate[] = "\
 HTTP/1.0 200 OK\n\
@@ -438,8 +439,8 @@ dcc_free_space %d MB\n\
                                dcc_stats.io_rate,
                                free_space_mb);
         dcc_set_nonblocking(acc_fd);
-        read(acc_fd, challenge, 1024); /* empty the receive queue */
-        write(acc_fd, reply, reply_len);
+        ret = read(acc_fd, challenge, 1024); /* empty the receive queue */
+        dcc_writex(acc_fd, reply, reply_len);
     }
 
     /* Don't think we need this to prevent RST anymore, since we read() now */
diff --git a/src/trace.c b/src/trace.c
index f23f94f..c5f148b 100644
--- a/src/trace.c
+++ b/src/trace.c
@@ -319,6 +319,7 @@ rs_logger_file(int flags, const char *fn, char const *fmt, va_list va,
     /* NOTE NO TRAILING NUL */
     char buf[4090];
     size_t len;
+    ssize_t ret;
 
     rs_format_msg(buf, sizeof buf, flags, fn, fmt, va);
 
@@ -327,7 +328,10 @@ rs_logger_file(int flags, const char *fn, char const *fmt, va_list va,
         len = (int) sizeof buf - 2;
     strcpy(&buf[len], "\n");
 
-    (void) write(log_fd, buf, len+1);
+    ret = write(log_fd, buf, len + 1);
+    if (ret == -1) {
+      ret = write(/* stderr */ 2, buf, len + 1);
+    }
 }
 
 
diff --git a/src/util.c b/src/util.c
index 0762867..4b26fa7 100644
--- a/src/util.c
+++ b/src/util.c
@@ -424,10 +424,17 @@ char *dcc_abspath(const char *path, int path_len)
     if (*path == '/')
         len = 0;
     else {
+        char *ret;
 #ifdef HAVE_GETCWD
-        getcwd(buf, sizeof buf);
+        ret = getcwd(buf, sizeof buf);
+        if (ret == NULL) {
+          rs_log_crit("getcwd failed: %s", strerror(errno));
+        }
 #else
-        getwd(buf);
+        ret = getwd(buf);
+        if (ret == NULL) {
+          rs_log_crit("getwd failed: %s", strerror(errno));
+        }
 #endif
         len = strlen(buf);
         if (len >= sizeof buf) {
@@ -675,8 +682,14 @@ void dcc_get_disk_io_stats(int *n_reads, int *n_writes) {
         kernel26 = 0;
     }
 
-    if (!kernel26) /* blast away 2 header lines in /proc/partitions */
-        fscanf(f, "%*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s");
+    if (!kernel26) /* blast away 2 header lines in /proc/partitions */ {
+        retval = fscanf(f,
+            "%*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s");
+        if (retval == EOF) {
+            fclose(f);
+            return;
+        }
+    }
 
     while (1) {
         if (kernel26)
@@ -707,7 +720,8 @@ void dcc_get_disk_io_stats(int *n_reads, int *n_writes) {
                 break;
 #endif
             /* assume the lines aren't longer that 1024 characters */
-            fgets(tmp, 1024, f);
+            if (fgets(tmp, 1024, f) == NULL)
+              break;
         }
     }