udhcpd: reduce stack usage by ~700 bytes. +28 bytes code size

[oweals/busybox.git] / printutils / lpr.c

diff --git a/printutils/lpr.c b/printutils/lpr.c
index 4f3b0247c80133c079de49102769e71b21b32ffa..fb7860d414e75330024a95575ae266867658189b 100644 (file)
--- a/printutils/lpr.c
+++ b/printutils/lpr.c
@@ -7,7 +7,7 @@
  * Original idea and code:
  *      Walter Harms <WHarms@bfs.de>
  *
- * Licensed under GPLv2, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2, see file LICENSE in this source tree.
  *
  * See RFC 1179 for protocol description.
  */
@@ -65,7 +65,7 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
        const char *server = "localhost"; // server[:port] of printer queue
        char *hostname;
        // N.B. IMHO getenv("USER") can be way easily spoofed!
-       const char *user = bb_getpwuid(NULL, -1, getuid());
+       const char *user = xuid2uname(getuid());
        unsigned job;
        unsigned opts;
        int fd;
@@ -149,6 +149,7 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
 
        // process files
        do {
+               unsigned cflen;
                int dfd;
                struct stat st;
                char *c;
@@ -194,23 +195,30 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
                );
                // delete possible "\nX\n" patterns
                c = controlfile;
+               cflen = (unsigned)strlen(controlfile);
                while ((c = strchr(c, '\n')) != NULL) {
-                       c++;
-                       while (c[0] && c[1] == '\n')
-                               memmove(c, c+2, strlen(c+1)); /* strlen(c+1) == strlen(c+2) + 1 */
+                       if (c[1] && c[2] == '\n') {
+                               /* can't use strcpy, results are undefined */
+                               memmove(c, c+2, cflen - (c-controlfile) - 1);
+                               cflen -= 2;
+                       } else {
+                               c++;
+                       }
                }
 
                // send control file
                if (opts & LPR_V)
                        bb_error_msg("sending control file");
+               /* "Acknowledgement processing must occur as usual
+                * after the command is sent." */
+               fdprintf(fd, "\x2" "%u c%s\n", cflen, remote_filename);
+               get_response_or_say_and_die(fd, "sending control file");
                /* "Once all of the contents have
                 * been delivered, an octet of zero bits is sent as
                 * an indication that the file being sent is complete.
                 * A second level of acknowledgement processing
                 * must occur at this point." */
-               fdprintf(fd, "\x2" "%u c%s\n" "%s" "%c",
-                               (unsigned)strlen(controlfile),
-                               remote_filename, controlfile, '\0');
+               full_write(fd, controlfile, cflen + 1); /* writes NUL byte too */
                get_response_or_say_and_die(fd, "sending control file");
 
                // send data file, with name "dfaXXX"
@@ -219,6 +227,7 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
                st.st_size = 0; /* paranoia: fstat may theoretically fail */
                fstat(dfd, &st);
                fdprintf(fd, "\x3" "%"OFF_FMT"u d%s\n", st.st_size, remote_filename);
+               get_response_or_say_and_die(fd, "sending data file");
                if (bb_copyfd_size(dfd, fd, st.st_size) != st.st_size) {
                        // We're screwed. We sent less bytes than we advertised.
                        bb_error_msg_and_die("local file changed size?!");