Curl_range: commonize FTP and FILE range handling

Closes #2205

5 files changed, 133 insertions, 120 deletions

diff --git a/lib/Makefile.inc b/lib/Makefile.inc
index ade22f13a..69f9b403d 100644
--- a/lib/Makefile.inc
+++ b/lib/Makefile.inc
@@ -46,7 +46,7 @@ LIB_CFILES = file.c timeval.c base64.c hostip.c progress.c formdata.c   \
   http_digest.c md4.c md5.c http_negotiate.c inet_pton.c strtoofft.c    \
   strerror.c amigaos.c hostasyn.c hostip4.c hostip6.c hostsyn.c         \
   inet_ntop.c parsedate.c select.c tftp.c splay.c strdup.c socks.c      \
-  ssh.c ssh-libssh.c curl_addrinfo.c socks_gssapi.c socks_sspi.c            \
+  ssh.c ssh-libssh.c curl_addrinfo.c socks_gssapi.c socks_sspi.c        \
   curl_sspi.c slist.c nonblock.c curl_memrchr.c imap.c pop3.c smtp.c    \
   pingpong.c rtsp.c curl_threads.c warnless.c hmac.c curl_rtmp.c        \
   openldap.c curl_gethostname.c gopher.c idn_win32.c                    \
@@ -54,7 +54,7 @@ LIB_CFILES = file.c timeval.c base64.c hostip.c progress.c formdata.c   \
   http_ntlm.c curl_ntlm_wb.c curl_ntlm_core.c curl_sasl.c rand.c        \
   curl_multibyte.c hostcheck.c conncache.c pipeline.c dotdot.c          \
   x509asn1.c http2.c smb.c curl_endian.c curl_des.c system_win32.c      \
-  mime.c sha256.c setopt.c curl_path.c curl_ctype.c
+  mime.c sha256.c setopt.c curl_path.c curl_ctype.c curl_range.c
 
 LIB_HFILES = arpa_telnet.h netrc.h file.h timeval.h hostip.h progress.h \
   formdata.h cookie.h http.h sendf.h ftp.h url.h dict.h if2ip.h         \
@@ -74,7 +74,7 @@ LIB_HFILES = arpa_telnet.h netrc.h file.h timeval.h hostip.h progress.h \
   curl_setup_once.h multihandle.h setup-vms.h pipeline.h dotdot.h       \
   x509asn1.h http2.h sigpipe.h smb.h curl_endian.h curl_des.h           \
   curl_printf.h system_win32.h rand.h mime.h curl_sha256.h setopt.h     \
-  curl_path.h curl_ctype.h
+  curl_path.h curl_ctype.h curl_range.h
 
 LIB_RCFILES = libcurl.rc
 
diff --git a/lib/curl_range.c b/lib/curl_range.c
new file mode 100644
index 000000000..e24215f4d
--- /dev/null
+++ b/lib/curl_range.c
@@ -0,0 +1,90 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+#include "curl_setup.h"
+#include <curl/curl.h>
+#include "curl_range.h"
+#include "sendf.h"
+#include "strtoofft.h"
+
+/* Only include this function if one or more of FTP, FILE are enabled. */
+#if !defined(CURL_DISABLE_FTP) && !defined(CURL_DISABLE_FILE)
+
+ /*
+  Check if this is a range download, and if so, set the internal variables
+  properly.
+ */
+CURLcode Curl_range(struct connectdata *conn)
+{
+  curl_off_t from, to;
+  curl_off_t totalsize = -1;
+  char *ptr;
+  char *ptr2;
+  struct Curl_easy *data = conn->data;
+
+  if(data->state.use_range && data->state.range) {
+    CURLofft from_t;
+    CURLofft to_t;
+    from_t = curlx_strtoofft(data->state.range, &ptr, 0, &from);
+    if(from_t == CURL_OFFT_FLOW)
+      return CURLE_RANGE_ERROR;
+    while(*ptr && (ISSPACE(*ptr) || (*ptr == '-')))
+      ptr++;
+    to_t = curlx_strtoofft(ptr, &ptr2, 0, &to);
+    if(to_t == CURL_OFFT_FLOW)
+      return CURLE_RANGE_ERROR;
+    if((to_t == CURL_OFFT_INVAL) && !from_t) {
+      /* X - */
+      data->state.resume_from = from;
+      DEBUGF(infof(data, "RANGE %" CURL_FORMAT_CURL_OFF_T " to end of file\n",
+                   from));
+    }
+    else if((from_t == CURL_OFFT_INVAL) && !to_t) {
+      /* -Y */
+      data->req.maxdownload = to;
+      data->state.resume_from = -to;
+      DEBUGF(infof(data, "RANGE the last %" CURL_FORMAT_CURL_OFF_T " bytes\n",
+                   to));
+    }
+    else {
+      /* X-Y */
+      totalsize = to-from;
+      if(totalsize == CURL_OFF_T_MAX)
+        /* this is too big to increase, so bail out */
+        return CURLE_RANGE_ERROR;
+      data->req.maxdownload = totalsize + 1; /* include last byte */
+      data->state.resume_from = from;
+      DEBUGF(infof(data, "RANGE from %" CURL_FORMAT_CURL_OFF_T
+                   " getting %" CURL_FORMAT_CURL_OFF_T " bytes\n",
+                   from, data->req.maxdownload));
+    }
+    DEBUGF(infof(data, "range-download from %" CURL_FORMAT_CURL_OFF_T
+                 " to %" CURL_FORMAT_CURL_OFF_T ", totally %"
+                 CURL_FORMAT_CURL_OFF_T " bytes\n",
+                 from, to, data->req.maxdownload));
+  }
+  else
+    data->req.maxdownload = -1;
+  return CURLE_OK;
+}
+
+#endif
diff --git a/lib/curl_range.h b/lib/curl_range.h
new file mode 100644
index 000000000..2350df992
--- /dev/null
+++ b/lib/curl_range.h
@@ -0,0 +1,30 @@
+#ifndef HEADER_CURL_RANGE_H
+#define HEADER_CURL_RANGE_H
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+#include "curl_setup.h"
+#include "urldata.h"
+
+CURLcode Curl_range(struct connectdata *conn);
+
+#endif /* HEADER_CURL_RANGE_H */
diff --git a/lib/file.c b/lib/file.c
index 0bbc0e180..ac611e6a1 100644
--- a/lib/file.c
+++ b/lib/file.c
@@ -61,6 +61,7 @@
 #include "url.h"
 #include "parsedate.h" /* for the week day and month names */
 #include "warnless.h"
+#include "curl_range.h"
 /* The last 3 #include files should be in this order */
 #include "curl_printf.h"
 #include "curl_memory.h"
@@ -125,65 +126,6 @@ static CURLcode file_setup_connection(struct connectdata *conn)
   return CURLE_OK;
 }
 
- /*
-  Check if this is a range download, and if so, set the internal variables
-  properly. This code is copied from the FTP implementation and might as
-  well be factored out.
- */
-static CURLcode file_range(struct connectdata *conn)
-{
-  curl_off_t from, to;
-  curl_off_t totalsize = -1;
-  char *ptr;
-  char *ptr2;
-  struct Curl_easy *data = conn->data;
-
-  if(data->state.use_range && data->state.range) {
-    CURLofft from_t;
-    CURLofft to_t;
-    from_t = curlx_strtoofft(data->state.range, &ptr, 0, &from);
-    if(from_t == CURL_OFFT_FLOW)
-      return CURLE_RANGE_ERROR;
-    while(*ptr && (ISSPACE(*ptr) || (*ptr == '-')))
-      ptr++;
-    to_t = curlx_strtoofft(ptr, &ptr2, 0, &to);
-    if(to_t == CURL_OFFT_FLOW)
-      return CURLE_RANGE_ERROR;
-    if((to_t == CURL_OFFT_INVAL) && !from_t) {
-      /* X - */
-      data->state.resume_from = from;
-      DEBUGF(infof(data, "RANGE %" CURL_FORMAT_CURL_OFF_T " to end of file\n",
-                   from));
-    }
-    else if((from_t == CURL_OFFT_INVAL) && !to_t) {
-      /* -Y */
-      data->req.maxdownload = to;
-      data->state.resume_from = -to;
-      DEBUGF(infof(data, "RANGE the last %" CURL_FORMAT_CURL_OFF_T " bytes\n",
-                   to));
-    }
-    else {
-      /* X-Y */
-      totalsize = to-from;
-      if(totalsize == CURL_OFF_T_MAX)
-        /* this is too big to increase, so bail out */
-        return CURLE_RANGE_ERROR;
-      data->req.maxdownload = totalsize + 1; /* include last byte */
-      data->state.resume_from = from;
-      DEBUGF(infof(data, "RANGE from %" CURL_FORMAT_CURL_OFF_T
-                   " getting %" CURL_FORMAT_CURL_OFF_T " bytes\n",
-                   from, data->req.maxdownload));
-    }
-    DEBUGF(infof(data, "range-download from %" CURL_FORMAT_CURL_OFF_T
-                 " to %" CURL_FORMAT_CURL_OFF_T ", totally %"
-                 CURL_FORMAT_CURL_OFF_T " bytes\n",
-                 from, to, data->req.maxdownload));
-  }
-  else
-    data->req.maxdownload = -1;
-  return CURLE_OK;
-}
-
 /*
  * file_connect() gets called from Curl_protocol_connect() to allow us to
  * do protocol-specific actions at connect-time.  We emulate a
@@ -514,7 +456,7 @@ static CURLcode file_do(struct connectdata *conn, bool *done)
   }
 
   /* Check whether file range has been specified */
-  file_range(conn);
+  Curl_range(conn);
 
   /* Adjust the start offset in case we want to get the N last bytes
    * of the stream iff the filesize could be determined */
diff --git a/lib/ftp.c b/lib/ftp.c
index 8042edf48..a9d83e682 100644
--- a/lib/ftp.c
+++ b/lib/ftp.c
@@ -59,6 +59,7 @@
 #include "ftp.h"
 #include "fileinfo.h"
 #include "ftplistparser.h"
+#include "curl_range.h"
 #include "curl_sec.h"
 #include "strtoofft.h"
 #include "strcase.h"
@@ -3463,62 +3464,6 @@ ftp_pasv_verbose(struct connectdata *conn,
 #endif
 
 /*
-  Check if this is a range download, and if so, set the internal variables
-  properly.
- */
-
-static CURLcode ftp_range(struct connectdata *conn)
-{
-  curl_off_t from, to;
-  char *ptr;
-  struct Curl_easy *data = conn->data;
-  struct ftp_conn *ftpc = &conn->proto.ftpc;
-
-  if(data->state.use_range && data->state.range) {
-    CURLofft from_t;
-    CURLofft to_t;
-    from_t = curlx_strtoofft(data->state.range, &ptr, 0, &from);
-    if(from_t == CURL_OFFT_FLOW)
-      return CURLE_RANGE_ERROR;
-    while(*ptr && (ISSPACE(*ptr) || (*ptr == '-')))
-      ptr++;
-    to_t = curlx_strtoofft(ptr, NULL, 0, &to);
-    if(to_t == CURL_OFFT_FLOW)
-      return CURLE_RANGE_ERROR;
-    if((to_t == CURL_OFFT_INVAL) && !from_t) {
-      /* X - */
-      data->state.resume_from = from;
-      DEBUGF(infof(conn->data, "FTP RANGE %" CURL_FORMAT_CURL_OFF_T
-                   " to end of file\n", from));
-    }
-    else if(!to_t && (from_t == CURL_OFFT_INVAL)) {
-      /* -Y */
-      data->req.maxdownload = to;
-      data->state.resume_from = -to;
-      DEBUGF(infof(conn->data, "FTP RANGE the last %" CURL_FORMAT_CURL_OFF_T
-                   " bytes\n", to));
-    }
-    else {
-      /* X-Y */
-      data->req.maxdownload = (to - from) + 1; /* include last byte */
-      data->state.resume_from = from;
-      DEBUGF(infof(conn->data, "FTP RANGE from %" CURL_FORMAT_CURL_OFF_T
-                   " getting %" CURL_FORMAT_CURL_OFF_T " bytes\n",
-                   from, data->req.maxdownload));
-    }
-    DEBUGF(infof(conn->data, "range-download from %" CURL_FORMAT_CURL_OFF_T
-                 " to %" CURL_FORMAT_CURL_OFF_T ", totally %"
-                 CURL_FORMAT_CURL_OFF_T " bytes\n",
-                 from, to, data->req.maxdownload));
-    ftpc->dont_check = TRUE; /* don't check for successful transfer */
-  }
-  else
-    data->req.maxdownload = -1;
-  return CURLE_OK;
-}
-
-
-/*
  * ftp_do_more()
  *
  * This function shall be called when the second FTP (data) connection is
@@ -3640,7 +3585,13 @@ static CURLcode ftp_do_more(struct connectdata *conn, int *completep)
       /* download */
       ftp->downloadsize = -1; /* unknown as of yet */
 
-      result = ftp_range(conn);
+      result = Curl_range(conn);
+
+      if(result == CURLE_OK && data->req.maxdownload >= 0) {
+        /* Don't check for successful transfer */
+        ftpc->dont_check = TRUE;
+      }
+
       if(result)
         ;
       else if(data->set.ftp_list_only || !ftpc->file) {