httpd: read cgi output with full_read, not safe_read

(avoids mangling of HTTP headers)

diff --git a/networking/httpd.c b/networking/httpd.c
index ff5c146726a1a8e2d9a9b774a452f25085d62680..bf3da36d99d760caf341aafbd6f6a08b472c0c01 100644 (file)
--- a/networking/httpd.c
+++ b/networking/httpd.c
@@ -91,10 +91,8 @@
  *
 */
 
-
 #include "busybox.h"
 
-
 static const char httpdVersion[] = "busybox httpd/1.35 6-Oct-2004";
 static const char default_path_httpd_conf[] = "/etc";
 static const char httpd_conf[] = "httpd.conf";
@@ -1065,7 +1063,7 @@ static int sendCgi(const char *url,
                 * It should not be decoded in any fashion. This variable
                 * should always be set when there is query information,
                 * regardless of command line decoding. */
-               /* (Older versions of bbox seemed to do some decoding) */
+               /* (Older versions of bbox seem to do some decoding) */
                setenv1("QUERY_STRING", config->query);
                setenv1("SERVER_SOFTWARE", httpdVersion);
                putenv("SERVER_PROTOCOL=HTTP/1.0");
@@ -1097,7 +1095,7 @@ static int sendCgi(const char *url,
                        goto error_execing_cgi;
                *script = '\0';
                if (chdir(realpath_buff) == 0) {
-                       // now run the program.  If it fails,
+                       // Now run the program.  If it fails,
                        // use _exit() so no destructors
                        // get called and make a mess.
 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
@@ -1210,21 +1208,22 @@ static int sendCgi(const char *url,
 #endif
 
                        /* There is something to read */
-                       count = safe_read(inFd, rbuf, PIPESIZE);
+                       /* NB: was safe_read. If it *has to be* safe_read, */
+                       /* please explain why in this comment... */
+                       count = full_read(inFd, rbuf, PIPESIZE);
                        if (count == 0)
                                break;  /* closed */
                        if (count > 0) {
                                if (firstLine) {
+                                       /* full_read (above) avoids
+                                        * "chopped up into small chunks" syndrome here */
                                        rbuf[count] = 0;
                                        /* check to see if the user script added headers */
                                        if (strncmp(rbuf, "HTTP/1.0 200 OK\r\n", 4) != 0) {
+                                               /* there is no "HTTP", do it ourself */
                                                full_write(s, "HTTP/1.0 200 OK\r\n", 17);
-                                       }
-                                       /* Sometimes CGI is writing to pipe in small chunks
-                                        * and we don't see Content-type (because the read
-                                        * is too short) and we emit bogus "text/plain"!
-                                        * Is it a bug or CGI *has to* write it in one piece? */
-                                       if (strstr(rbuf, "ontent-") == 0) {
+                                       } /* hmm, maybe 'else if'? */
+                                       if (!strstr(rbuf, "ontent-")) {
                                                full_write(s, "Content-type: text/plain\r\n\r\n", 28);
                                        }
                                        firstLine = 0;