wget: code shrink by splitting main() into easier-to-optimize functions

function                                             old     new   delta
retrieve_file_data                                     -     356    +356
wget_main                                           2793    2326    -467
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/1 up/down: 356/-467)         Total: -111 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 174 insertions, 161 deletions

diff --git a/networking/wget.c b/networking/wget.c
index ca3acd085..5e387891a 100644
--- a/networking/wget.c
+++ b/networking/wget.c
@@ -32,7 +32,8 @@ struct globals {
         unsigned lastupdate_sec;
         unsigned start_sec;
 #endif
-        smallint chunked;             /* chunked transfer encoding */
+        smallint chunked;         /* chunked transfer encoding */
+        smallint got_clen;        /* got content-length: from server  */
 };
 #define G (*(struct globals*)&bb_common_bufsiz1)
 struct BUG_G_too_big {
@@ -46,7 +47,6 @@ struct BUG_G_too_big {
 #define curfile         (G.curfile        )
 #define lastupdate_sec  (G.lastupdate_sec )
 #define start_sec       (G.start_sec      )
-#define chunked         (G.chunked        )
 #define INIT_G() do { } while (0)
 
 
@@ -79,7 +79,7 @@ static void progress_meter(int flag)
         }
 
         ratio = 100;
-        if (totalsize != 0 && !chunked) {
+        if (totalsize != 0 && !G.chunked) {
                 /* long long helps to have it working even if !LFS */
                 ratio = (unsigned) (100ULL * (transferred+beg_range) / totalsize);
                 if (ratio > 100) ratio = 100;
@@ -127,7 +127,7 @@ static void progress_meter(int flag)
                 fprintf(stderr, " - stalled -");
         } else {
                 off_t to_download = totalsize - beg_range;
-                if (transferred <= 0 || (int)elapsed <= 0 || transferred > to_download || chunked) {
+                if (transferred <= 0 || (int)elapsed <= 0 || transferred > to_download || G.chunked) {
                         fprintf(stderr, "--:--:-- ETA");
                 } else {
                         /* to_download / (transferred/elapsed) - elapsed: */
@@ -239,7 +239,6 @@ static char *base64enc_512(char buf[512], const char *str)
 }
 #endif
 
-
 static FILE *open_socket(len_and_sockaddr *lsa)
 {
         FILE *fp;
@@ -253,7 +252,6 @@ static FILE *open_socket(len_and_sockaddr *lsa)
         return fp;
 }
 
-
 static int ftpcmd(const char *s1, const char *s2, FILE *fp, char *buf)
 {
         int result;
@@ -281,7 +279,6 @@ static int ftpcmd(const char *s1, const char *s2, FILE *fp, char *buf)
         return result;
 }
 
-
 static void parse_url(char *src_url, struct host_info *h)
 {
         char *url, *p, *sp;
@@ -340,7 +337,6 @@ static void parse_url(char *src_url, struct host_info *h)
         sp = h->host;
 }
 
-
 static char *gethdr(char *buf, size_t bufsiz, FILE *fp /*, int *istrunc*/)
 {
         char *s, *hdrval;
@@ -380,7 +376,7 @@ static char *gethdr(char *buf, size_t bufsiz, FILE *fp /*, int *istrunc*/)
                 return hdrval;
         }
 
-        /* Rats! The buffer isn't big enough to hold the entire header value. */
+        /* Rats! The buffer isn't big enough to hold the entire header value */
         while (c = getc(fp), c != EOF && c != '\n')
                 continue;
         /* *istrunc = 1; */
@@ -425,30 +421,171 @@ static char *URL_escape(const char *str)
 }
 #endif
 
+static FILE* prepare_ftp_session(FILE **dfpp, struct host_info *target, len_and_sockaddr *lsa)
+{
+        char buf[512];
+        FILE *sfp;
+        char *str;
+        int port;
+
+        if (!target->user)
+                target->user = xstrdup("anonymous:busybox@");
+
+        sfp = open_socket(lsa);
+        if (ftpcmd(NULL, NULL, sfp, buf) != 220)
+                bb_error_msg_and_die("%s", buf+4);
+
+        /*
+         * Splitting username:password pair,
+         * trying to log in
+         */
+        str = strchr(target->user, ':');
+        if (str)
+                *str++ = '\0';
+        switch (ftpcmd("USER ", target->user, sfp, buf)) {
+        case 230:
+                break;
+        case 331:
+                if (ftpcmd("PASS ", str, sfp, buf) == 230)
+                        break;
+                /* fall through (failed login) */
+        default:
+                bb_error_msg_and_die("ftp login: %s", buf+4);
+        }
+
+        ftpcmd("TYPE I", NULL, sfp, buf);
+
+        /*
+         * Querying file size
+         */
+        if (ftpcmd("SIZE ", target->path, sfp, buf) == 213) {
+                content_len = BB_STRTOOFF(buf+4, NULL, 10);
+                if (errno || content_len < 0) {
+                        bb_error_msg_and_die("SIZE value is garbage");
+                }
+                G.got_clen = 1;
+        }
+
+        /*
+         * Entering passive mode
+         */
+        if (ftpcmd("PASV", NULL, sfp, buf) != 227) {
+ pasv_error:
+                bb_error_msg_and_die("bad response to %s: %s", "PASV", buf);
+        }
+        // Response is "227 garbageN1,N2,N3,N4,P1,P2[)garbage]
+        // Server's IP is N1.N2.N3.N4 (we ignore it)
+        // Server's port for data connection is P1*256+P2
+        str = strrchr(buf, ')');
+        if (str) str[0] = '\0';
+        str = strrchr(buf, ',');
+        if (!str) goto pasv_error;
+        port = xatou_range(str+1, 0, 255);
+        *str = '\0';
+        str = strrchr(buf, ',');
+        if (!str) goto pasv_error;
+        port += xatou_range(str+1, 0, 255) * 256;
+        set_nport(lsa, htons(port));
+
+        *dfpp = open_socket(lsa);
+
+        if (beg_range) {
+                sprintf(buf, "REST %"OFF_FMT"d", beg_range);
+                if (ftpcmd(buf, NULL, sfp, buf) == 350)
+                        content_len -= beg_range;
+        }
+
+        if (ftpcmd("RETR ", target->path, sfp, buf) > 150)
+                bb_error_msg_and_die("bad response to %s: %s", "RETR", buf);
+
+        return sfp;
+}
+
+/* Must match option string! */
+enum {
+        WGET_OPT_CONTINUE   = (1 << 0),
+        WGET_OPT_SPIDER     = (1 << 1),
+        WGET_OPT_QUIET      = (1 << 2),
+        WGET_OPT_OUTNAME    = (1 << 3),
+        WGET_OPT_PREFIX     = (1 << 4),
+        WGET_OPT_PROXY      = (1 << 5),
+        WGET_OPT_USER_AGENT = (1 << 6),
+        WGET_OPT_RETRIES    = (1 << 7),
+        WGET_OPT_NETWORK_READ_TIMEOUT = (1 << 8),
+        WGET_OPT_PASSIVE    = (1 << 9),
+        WGET_OPT_HEADER     = (1 << 10) * ENABLE_FEATURE_WGET_LONG_OPTIONS,
+        WGET_OPT_POST_DATA  = (1 << 11) * ENABLE_FEATURE_WGET_LONG_OPTIONS,
+};
+
+static void NOINLINE retrieve_file_data(FILE *dfp, int output_fd)
+{
+        char buf[512];
+
+        if (!(option_mask32 & WGET_OPT_QUIET))
+                progress_meter(-1);
+
+        if (G.chunked)
+                goto get_clen;
+
+        /* Loops only if chunked */
+        while (1) {
+                while (content_len > 0 || !G.got_clen) {
+                        int n;
+                        unsigned rdsz = sizeof(buf);
+
+                        if (content_len < sizeof(buf) && (G.chunked || G.got_clen))
+                                rdsz = (unsigned)content_len;
+                        n = safe_fread(buf, rdsz, dfp);
+                        if (n <= 0) {
+                                if (ferror(dfp)) {
+                                        /* perror will not work: ferror doesn't set errno */
+                                        bb_error_msg_and_die(bb_msg_read_error);
+                                }
+                                break;
+                        }
+                        xwrite(output_fd, buf, n);
+#if ENABLE_FEATURE_WGET_STATUSBAR
+                        transferred += n;
+#endif
+                        if (G.got_clen)
+                                content_len -= n;
+                }
+
+                if (!G.chunked)
+                        break;
+
+                safe_fgets(buf, sizeof(buf), dfp); /* This is a newline */
+ get_clen:
+                safe_fgets(buf, sizeof(buf), dfp);
+                content_len = STRTOOFF(buf, NULL, 16);
+                /* FIXME: error check? */
+                if (content_len == 0)
+                        break; /* all done! */
+        }
+
+        if (!(option_mask32 & WGET_OPT_QUIET))
+                progress_meter(0);
+}
+
 int wget_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int wget_main(int argc UNUSED_PARAM, char **argv)
 {
         char buf[512];
         struct host_info server, target;
         len_and_sockaddr *lsa;
-        int status;
-        int port;
-        int try = 5;
         unsigned opt;
-        char *str;
-        char *proxy = 0;
+        char *proxy = NULL;
         char *dir_prefix = NULL;
 #if ENABLE_FEATURE_WGET_LONG_OPTIONS
         char *post_data;
         char *extra_headers = NULL;
         llist_t *headers_llist = NULL;
 #endif
-        FILE *sfp = NULL;               /* socket to web/ftp server         */
+        FILE *sfp;                      /* socket to web/ftp server         */
         FILE *dfp;                      /* socket to ftp server (data)      */
         char *fname_out;                /* where to direct output (-O)      */
-        bool got_clen = 0;              /* got content-length: from server  */
         int output_fd = -1;
-        bool use_proxy = 1;             /* Use proxies if env vars are set  */
+        bool use_proxy;                 /* Use proxies if env vars are set  */
         const char *proxy_flag = "on";  /* Use proxies if env vars are set  */
         const char *user_agent = "Wget";/* "User-Agent" header field        */
 
@@ -457,20 +594,6 @@ int wget_main(int argc UNUSED_PARAM, char **argv)
         enum {
                 KEY_content_length = 1, KEY_transfer_encoding, KEY_chunked, KEY_location
         };
-        enum {
-                WGET_OPT_CONTINUE   = (1 << 0),
-                WGET_OPT_SPIDER     = (1 << 1),
-                WGET_OPT_QUIET      = (1 << 2),
-                WGET_OPT_OUTNAME    = (1 << 3),
-                WGET_OPT_PREFIX     = (1 << 4),
-                WGET_OPT_PROXY      = (1 << 5),
-                WGET_OPT_USER_AGENT = (1 << 6),
-                WGET_OPT_RETRIES    = (1 << 7),
-                WGET_OPT_NETWORK_READ_TIMEOUT = (1 << 8),
-                WGET_OPT_PASSIVE    = (1 << 9),
-                WGET_OPT_HEADER     = (1 << 10) * ENABLE_FEATURE_WGET_LONG_OPTIONS,
-                WGET_OPT_POST_DATA  = (1 << 11) * ENABLE_FEATURE_WGET_LONG_OPTIONS,
-        };
 #if ENABLE_FEATURE_WGET_LONG_OPTIONS
         static const char wget_longopts[] ALIGN1 =
                 /* name, has_arg, val */
@@ -506,10 +629,6 @@ int wget_main(int argc UNUSED_PARAM, char **argv)
                                 IF_FEATURE_WGET_LONG_OPTIONS(, &headers_llist)
                                 IF_FEATURE_WGET_LONG_OPTIONS(, &post_data)
                                 );
-        if (strcmp(proxy_flag, "off") == 0) {
-                /* Use the proxy if necessary */
-                use_proxy = 0;
-        }
 #if ENABLE_FEATURE_WGET_LONG_OPTIONS
         if (headers_llist) {
                 int size = 1;
@@ -526,11 +645,13 @@ int wget_main(int argc UNUSED_PARAM, char **argv)
         }
 #endif
 
+        /* TODO: compat issue: should handle "wget URL1 URL2..." */
         parse_url(argv[optind], &target);
         server.host = target.host;
         server.port = target.port;
 
         /* Use the proxy if necessary */
+        use_proxy = (strcmp(proxy_flag, "off") != 0);
         if (use_proxy) {
                 proxy = getenv(target.is_ftp ? "ftp_proxy" : "http_proxy");
                 if (proxy && *proxy) {
@@ -562,7 +683,8 @@ int wget_main(int argc UNUSED_PARAM, char **argv)
 
         /* Impossible?
         if ((opt & WGET_OPT_CONTINUE) && !fname_out)
-                bb_error_msg_and_die("cannot specify continue (-c) without a filename (-O)"); */
+                bb_error_msg_and_die("cannot specify continue (-c) without a filename (-O)");
+        */
 
         /* Determine where to start transfer */
         if (opt & WGET_OPT_CONTINUE) {
@@ -571,7 +693,7 @@ int wget_main(int argc UNUSED_PARAM, char **argv)
                         beg_range = xlseek(output_fd, 0, SEEK_END);
                 }
                 /* File doesn't exist. We do not create file here yet.
-                   We are not sure it exists on remove side */
+                 * We are not sure it exists on remove side */
         }
 
         /* We want to do exactly _one_ DNS lookup, since some
@@ -584,13 +706,20 @@ int wget_main(int argc UNUSED_PARAM, char **argv)
                 /* We leak result of xmalloc_sockaddr2dotted */
         }
 
+        /* G.got_clen = 0; - already is */
+        sfp = NULL;
         if (use_proxy || !target.is_ftp) {
                 /*
                  *  HTTP session
                  */
+                int status;
+                int try = 5;
+
                 do {
-                        got_clen = 0;
-                        chunked = 0;
+                        char *str;
+
+                        G.got_clen = 0;
+                        G.chunked = 0;
 
                         if (!--try)
                                 bb_error_msg_and_die("too many redirections");
@@ -599,7 +728,7 @@ int wget_main(int argc UNUSED_PARAM, char **argv)
                         if (sfp) fclose(sfp);
                         sfp = open_socket(lsa);
 
-                        /* Send HTTP request.  */
+                        /* Send HTTP request */
                         if (use_proxy) {
                                 fprintf(sfp, "GET %stp://%s/%s HTTP/1.1\r\n",
                                         target.is_ftp ? "f" : "ht", target.host,
@@ -710,20 +839,20 @@ However, in real world it was observed that some web servers
                          * Retrieve HTTP headers.
                          */
                         while ((str = gethdr(buf, sizeof(buf), sfp /*, &n*/)) != NULL) {
-                                /* gethdr did already convert the "FOO:" string to lowercase */
+                                /* gethdr converted "FOO:" string to lowercase */
                                 smalluint key = index_in_strings(keywords, *&buf) + 1;
                                 if (key == KEY_content_length) {
                                         content_len = BB_STRTOOFF(str, NULL, 10);
                                         if (errno || content_len < 0) {
                                                 bb_error_msg_and_die("content-length %s is garbage", str);
                                         }
-                                        got_clen = 1;
+                                        G.got_clen = 1;
                                         continue;
                                 }
                                 if (key == KEY_transfer_encoding) {
                                         if (index_in_strings(keywords, str_tolower(str)) + 1 != KEY_chunked)
                                                 bb_error_msg_and_die("transfer encoding '%s' is not supported", str);
-                                        chunked = got_clen = 1;
+                                        G.chunked = G.got_clen = 1;
                                 }
                                 if (key == KEY_location) {
                                         if (str[0] == '/')
@@ -746,78 +875,10 @@ However, in real world it was observed that some web servers
                 dfp = sfp;
 
         } else {
-
                 /*
                  *  FTP session
                  */
-                if (!target.user)
-                        target.user = xstrdup("anonymous:busybox@");
-
-                sfp = open_socket(lsa);
-                if (ftpcmd(NULL, NULL, sfp, buf) != 220)
-                        bb_error_msg_and_die("%s", buf+4);
-
-                /*
-                 * Splitting username:password pair,
-                 * trying to log in
-                 */
-                str = strchr(target.user, ':');
-                if (str)
-                        *(str++) = '\0';
-                switch (ftpcmd("USER ", target.user, sfp, buf)) {
-                case 230:
-                        break;
-                case 331:
-                        if (ftpcmd("PASS ", str, sfp, buf) == 230)
-                                break;
-                        /* fall through (failed login) */
-                default:
-                        bb_error_msg_and_die("ftp login: %s", buf+4);
-                }
-
-                ftpcmd("TYPE I", NULL, sfp, buf);
-
-                /*
-                 * Querying file size
-                 */
-                if (ftpcmd("SIZE ", target.path, sfp, buf) == 213) {
-                        content_len = BB_STRTOOFF(buf+4, NULL, 10);
-                        if (errno || content_len < 0) {
-                                bb_error_msg_and_die("SIZE value is garbage");
-                        }
-                        got_clen = 1;
-                }
-
-                /*
-                 * Entering passive mode
-                 */
-                if (ftpcmd("PASV", NULL, sfp, buf) != 227) {
- pasv_error:
-                        bb_error_msg_and_die("bad response to %s: %s", "PASV", buf);
-                }
-                // Response is "227 garbageN1,N2,N3,N4,P1,P2[)garbage]
-                // Server's IP is N1.N2.N3.N4 (we ignore it)
-                // Server's port for data connection is P1*256+P2
-                str = strrchr(buf, ')');
-                if (str) str[0] = '\0';
-                str = strrchr(buf, ',');
-                if (!str) goto pasv_error;
-                port = xatou_range(str+1, 0, 255);
-                *str = '\0';
-                str = strrchr(buf, ',');
-                if (!str) goto pasv_error;
-                port += xatou_range(str+1, 0, 255) * 256;
-                set_nport(lsa, htons(port));
-                dfp = open_socket(lsa);
-
-                if (beg_range) {
-                        sprintf(buf, "REST %"OFF_FMT"d", beg_range);
-                        if (ftpcmd(buf, NULL, sfp, buf) == 350)
-                                content_len -= beg_range;
-                }
-
-                if (ftpcmd("RETR ", target.path, sfp, buf) > 150)
-                        bb_error_msg_and_die("bad response to %s: %s", "RETR", buf);
+                sfp = prepare_ftp_session(&dfp, &target, lsa);
         }
 
         if (opt & WGET_OPT_SPIDER) {
@@ -826,11 +887,6 @@ However, in real world it was observed that some web servers
                 return EXIT_SUCCESS;
         }
 
-        /*
-         * Retrieve file
-         */
-
-        /* Do it before progress_meter (want to have nice error message) */
         if (output_fd < 0) {
                 int o_flags = O_WRONLY | O_CREAT | O_TRUNC | O_EXCL;
                 /* compat with wget: -O FILE can overwrite */
@@ -839,50 +895,7 @@ However, in real world it was observed that some web servers
                 output_fd = xopen(fname_out, o_flags);
         }
 
-        if (!(opt & WGET_OPT_QUIET))
-                progress_meter(-1);
-
-        if (chunked)
-                goto get_clen;
-
-        /* Loops only if chunked */
-        while (1) {
-                while (content_len > 0 || !got_clen) {
-                        int n;
-                        unsigned rdsz = sizeof(buf);
-
-                        if (content_len < sizeof(buf) && (chunked || got_clen))
-                                rdsz = (unsigned)content_len;
-                        n = safe_fread(buf, rdsz, dfp);
-                        if (n <= 0) {
-                                if (ferror(dfp)) {
-                                        /* perror will not work: ferror doesn't set errno */
-                                        bb_error_msg_and_die(bb_msg_read_error);
-                                }
-                                break;
-                        }
-                        xwrite(output_fd, buf, n);
-#if ENABLE_FEATURE_WGET_STATUSBAR
-                        transferred += n;
-#endif
-                        if (got_clen)
-                                content_len -= n;
-                }
-
-                if (!chunked)
-                        break;
-
-                safe_fgets(buf, sizeof(buf), dfp); /* This is a newline */
- get_clen:
-                safe_fgets(buf, sizeof(buf), dfp);
-                content_len = STRTOOFF(buf, NULL, 16);
-                /* FIXME: error check? */
-                if (content_len == 0)
-                        break; /* all done! */
-        }
-
-        if (!(opt & WGET_OPT_QUIET))
-                progress_meter(0);
+        retrieve_file_data(dfp, output_fd);
 
         if ((use_proxy == 0) && target.is_ftp) {
                 fclose(dfp);