curl 2020-06-23 (e9db32a0)

Code extracted from:

    https://github.com/curl/curl.git

at commit e9db32a09af03f27e86d1251a9e68e9b7486d371 (curl-7_71_0).

1 files changed, 213 insertions, 65 deletions

diff --git a/lib/mime.c b/lib/mime.c
index 2571287..4a87c4a 100644
--- a/lib/mime.c
+++ b/lib/mime.c
@@ -26,6 +26,7 @@
 
 #include "mime.h"
 #include "non-ascii.h"
+#include "warnless.h"
 #include "urldata.h"
 #include "sendf.h"
 
@@ -52,6 +53,10 @@
 
 
 #define READ_ERROR                      ((size_t) -1)
+#define STOP_FILLING                    ((size_t) -2)
+
+static size_t mime_subparts_read(char *buffer, size_t size, size_t nitems,
+                                 void *instream, bool *hasread);
 
 /* Encoders. */
 static size_t encoder_nop_read(char *buffer, size_t size, bool ateof,
@@ -66,7 +71,7 @@ static size_t encoder_qp_read(char *buffer, size_t size, bool ateof,
                               curl_mimepart *part);
 static curl_off_t encoder_qp_size(curl_mimepart *part);
 
-static const mime_encoder encoders[] = {
+static const struct mime_encoder encoders[] = {
   {"binary", encoder_nop_read, encoder_nop_size},
   {"8bit", encoder_nop_read, encoder_nop_size},
   {"7bit", encoder_7bit_read, encoder_nop_size},
@@ -264,7 +269,8 @@ static char *Curl_basename(char *path)
 
 
 /* Set readback state. */
-static void mimesetstate(mime_state *state, enum mimestate tok, void *ptr)
+static void mimesetstate(struct mime_state *state,
+                         enum mimestate tok, void *ptr)
 {
   state->state = tok;
   state->ptr = ptr;
@@ -337,7 +343,7 @@ static char *strippath(const char *fullfile)
 }
 
 /* Initialize data encoder state. */
-static void cleanup_encoder_state(mime_encoder_state *p)
+static void cleanup_encoder_state(struct mime_encoder_state *p)
 {
   p->pos = 0;
   p->bufbeg = 0;
@@ -347,17 +353,22 @@ static void cleanup_encoder_state(mime_encoder_state *p)
 
 /* Dummy encoder. This is used for 8bit and binary content encodings. */
 static size_t encoder_nop_read(char *buffer, size_t size, bool ateof,
-                               curl_mimepart *part)
+                               struct curl_mimepart *part)
 {
-  mime_encoder_state *st = &part->encstate;
+  struct mime_encoder_state *st = &part->encstate;
   size_t insize = st->bufend - st->bufbeg;
 
   (void) ateof;
 
+  if(!size)
+    return STOP_FILLING;
+
   if(size > insize)
     size = insize;
+
   if(size)
-    memcpy(buffer, st->buf, size);
+    memcpy(buffer, st->buf + st->bufbeg, size);
+
   st->bufbeg += size;
   return size;
 }
@@ -372,11 +383,14 @@ static curl_off_t encoder_nop_size(curl_mimepart *part)
 static size_t encoder_7bit_read(char *buffer, size_t size, bool ateof,
                                 curl_mimepart *part)
 {
-  mime_encoder_state *st = &part->encstate;
+  struct mime_encoder_state *st = &part->encstate;
   size_t cursize = st->bufend - st->bufbeg;
 
   (void) ateof;
 
+  if(!size)
+    return STOP_FILLING;
+
   if(size > cursize)
     size = cursize;
 
@@ -395,7 +409,7 @@ static size_t encoder_7bit_read(char *buffer, size_t size, bool ateof,
 static size_t encoder_base64_read(char *buffer, size_t size, bool ateof,
                                 curl_mimepart *part)
 {
-  mime_encoder_state *st = &part->encstate;
+  struct mime_encoder_state *st = &part->encstate;
   size_t cursize = 0;
   int i;
   char *ptr = buffer;
@@ -404,8 +418,11 @@ static size_t encoder_base64_read(char *buffer, size_t size, bool ateof,
     /* Line full ? */
     if(st->pos > MAX_ENCODED_LINE_LENGTH - 4) {
       /* Yes, we need 2 characters for CRLF. */
-      if(size < 2)
+      if(size < 2) {
+        if(!cursize)
+          return STOP_FILLING;
         break;
+      }
       *ptr++ = '\r';
       *ptr++ = '\n';
       st->pos = 0;
@@ -414,7 +431,12 @@ static size_t encoder_base64_read(char *buffer, size_t size, bool ateof,
     }
 
     /* Be sure there is enough space and input data for a base64 group. */
-    if(size < 4 || st->bufend - st->bufbeg < 3)
+    if(size < 4) {
+      if(!cursize)
+        return STOP_FILLING;
+      break;
+    }
+    if(st->bufend - st->bufbeg < 3)
       break;
 
     /* Encode three bytes as four characters. */
@@ -431,25 +453,31 @@ static size_t encoder_base64_read(char *buffer, size_t size, bool ateof,
   }
 
   /* If at eof, we have to flush the buffered data. */
-  if(ateof && size >= 4) {
-    /* Buffered data size can only be 0, 1 or 2. */
-    ptr[2] = ptr[3] = '=';
-    i = 0;
-    switch(st->bufend - st->bufbeg) {
-    case 2:
-      i = (st->buf[st->bufbeg + 1] & 0xFF) << 8;
-      /* FALLTHROUGH */
-    case 1:
-      i |= (st->buf[st->bufbeg] & 0xFF) << 16;
-      ptr[0] = base64[(i >> 18) & 0x3F];
-      ptr[1] = base64[(i >> 12) & 0x3F];
-      if(++st->bufbeg != st->bufend) {
-        ptr[2] = base64[(i >> 6) & 0x3F];
-        st->bufbeg++;
+  if(ateof) {
+    if(size < 4) {
+      if(!cursize)
+        return STOP_FILLING;
+    }
+    else {
+      /* Buffered data size can only be 0, 1 or 2. */
+      ptr[2] = ptr[3] = '=';
+      i = 0;
+      switch(st->bufend - st->bufbeg) {
+      case 2:
+        i = (st->buf[st->bufbeg + 1] & 0xFF) << 8;
+        /* FALLTHROUGH */
+      case 1:
+        i |= (st->buf[st->bufbeg] & 0xFF) << 16;
+        ptr[0] = base64[(i >> 18) & 0x3F];
+        ptr[1] = base64[(i >> 12) & 0x3F];
+        if(++st->bufbeg != st->bufend) {
+          ptr[2] = base64[(i >> 6) & 0x3F];
+          st->bufbeg++;
+        }
+        cursize += 4;
+        st->pos += 4;
+        break;
       }
-      cursize += 4;
-      st->pos += 4;
-      break;
     }
   }
 
@@ -485,7 +513,7 @@ static curl_off_t encoder_base64_size(curl_mimepart *part)
  * Check if a CRLF or end of data is in input buffer at current position + n.
  * Return -1 if more data needed, 1 if CRLF or end of data, else 0.
  */
-static int qp_lookahead_eol(mime_encoder_state *st, int ateof, size_t n)
+static int qp_lookahead_eol(struct mime_encoder_state *st, int ateof, size_t n)
 {
   n += st->bufbeg;
   if(n >= st->bufend && ateof)
@@ -502,7 +530,7 @@ static int qp_lookahead_eol(mime_encoder_state *st, int ateof, size_t n)
 static size_t encoder_qp_read(char *buffer, size_t size, bool ateof,
                               curl_mimepart *part)
 {
-  mime_encoder_state *st = &part->encstate;
+  struct mime_encoder_state *st = &part->encstate;
   char *ptr = buffer;
   size_t cursize = 0;
   int softlinebreak;
@@ -567,7 +595,6 @@ static size_t encoder_qp_read(char *buffer, size_t size, bool ateof,
         switch(qp_lookahead_eol(st, ateof, consumed)) {
         case -1:        /* Need more data. */
           return cursize;
-          break;
         case 0:         /* Not followed by a CRLF. */
           softlinebreak = 1;
           break;
@@ -581,8 +608,11 @@ static size_t encoder_qp_read(char *buffer, size_t size, bool ateof,
     }
 
     /* If the output buffer would overflow, do not store. */
-    if(len > size)
+    if(len > size) {
+      if(!cursize)
+        return STOP_FILLING;
       break;
+    }
 
     /* Append to output buffer. */
     memcpy(ptr, buf, len);
@@ -612,16 +642,18 @@ static size_t mime_mem_read(char *buffer, size_t size, size_t nitems,
                             void *instream)
 {
   curl_mimepart *part = (curl_mimepart *) instream;
-  size_t sz = (size_t) part->datasize - part->state.offset;
+  size_t sz = curlx_sotouz(part->datasize - part->state.offset);
   (void) size;   /* Always 1.*/
 
+  if(!nitems)
+    return STOP_FILLING;
+
   if(sz > nitems)
     sz = nitems;
 
   if(sz)
-    memcpy(buffer, (char *) &part->data[part->state.offset], sz);
+    memcpy(buffer, part->data + curlx_sotouz(part->state.offset), sz);
 
-  part->state.offset += sz;
   return sz;
 }
 
@@ -641,7 +673,7 @@ static int mime_mem_seek(void *instream, curl_off_t offset, int whence)
   if(offset < 0 || offset > part->datasize)
     return CURL_SEEKFUNC_FAIL;
 
-  part->state.offset = (size_t) offset;
+  part->state.offset = offset;
   return CURL_SEEKFUNC_OK;
 }
 
@@ -653,7 +685,7 @@ static void mime_mem_free(void *ptr)
 
 /* Named file callbacks. */
 /* Argument is a pointer to the mime part. */
-static int mime_open_file(curl_mimepart * part)
+static int mime_open_file(curl_mimepart *part)
 {
   /* Open a MIMEKIND_FILE part. */
 
@@ -668,6 +700,9 @@ static size_t mime_file_read(char *buffer, size_t size, size_t nitems,
 {
   curl_mimepart *part = (curl_mimepart *) instream;
 
+  if(!nitems)
+    return STOP_FILLING;
+
   if(mime_open_file(part))
     return READ_ERROR;
 
@@ -705,21 +740,22 @@ static void mime_file_free(void *ptr)
 /* Argument is a pointer to the mime structure. */
 
 /* Readback a byte string segment. */
-static size_t readback_bytes(mime_state *state,
+static size_t readback_bytes(struct mime_state *state,
                              char *buffer, size_t bufsize,
                              const char *bytes, size_t numbytes,
                              const char *trail)
 {
   size_t sz;
+  size_t offset = curlx_sotouz(state->offset);
 
-  if(numbytes > state->offset) {
-    sz = numbytes - state->offset;
-    bytes += state->offset;
+  if(numbytes > offset) {
+    sz = numbytes - offset;
+    bytes += offset;
   }
   else {
     size_t tsz = strlen(trail);
 
-    sz = state->offset - numbytes;
+    sz = offset - numbytes;
     if(sz >= tsz)
       return 0;
     bytes = trail + sz;
@@ -736,25 +772,79 @@ static size_t readback_bytes(mime_state *state,
 
 /* Read a non-encoded part content. */
 static size_t read_part_content(curl_mimepart *part,
-                                char *buffer, size_t bufsize)
+                                char *buffer, size_t bufsize, bool *hasread)
 {
   size_t sz = 0;
 
-  if(part->readfunc)
-    sz = part->readfunc(buffer, 1, bufsize, part->arg);
+  switch(part->lastreadstatus) {
+  case 0:
+  case CURL_READFUNC_ABORT:
+  case CURL_READFUNC_PAUSE:
+  case READ_ERROR:
+    return part->lastreadstatus;
+  default:
+    break;
+  }
+
+  /* If we can determine we are at end of part data, spare a read. */
+  if(part->datasize != (curl_off_t) -1 &&
+     part->state.offset >= part->datasize) {
+    /* sz is already zero. */
+  }
+  else {
+    switch(part->kind) {
+    case MIMEKIND_MULTIPART:
+      /*
+       * Cannot be processed as other kinds since read function requires
+       * an additional parameter and is highly recursive.
+       */
+       sz = mime_subparts_read(buffer, 1, bufsize, part->arg, hasread);
+       break;
+    case MIMEKIND_FILE:
+      if(part->fp && feof(part->fp))
+        break;  /* At EOF. */
+      /* FALLTHROUGH */
+    default:
+      if(part->readfunc) {
+        if(!(part->flags & MIME_FAST_READ)) {
+          if(*hasread)
+            return STOP_FILLING;
+          *hasread = TRUE;
+        }
+        sz = part->readfunc(buffer, 1, bufsize, part->arg);
+      }
+      break;
+    }
+  }
+
+  switch(sz) {
+  case STOP_FILLING:
+    break;
+  case 0:
+  case CURL_READFUNC_ABORT:
+  case CURL_READFUNC_PAUSE:
+  case READ_ERROR:
+    part->lastreadstatus = sz;
+    break;
+  default:
+    part->state.offset += sz;
+    part->lastreadstatus = sz;
+    break;
+  }
+
   return sz;
 }
 
 /* Read and encode part content. */
-static size_t read_encoded_part_content(curl_mimepart *part,
-                                        char *buffer, size_t bufsize)
+static size_t read_encoded_part_content(curl_mimepart *part, char *buffer,
+                                        size_t bufsize, bool *hasread)
 {
-  mime_encoder_state *st = &part->encstate;
+  struct mime_encoder_state *st = &part->encstate;
   size_t cursize = 0;
   size_t sz;
   bool ateof = FALSE;
 
-  while(bufsize) {
+  for(;;) {
     if(st->bufbeg < st->bufend || ateof) {
       /* Encode buffered data. */
       sz = part->encoder->encodefunc(buffer, bufsize, ateof, part);
@@ -763,9 +853,8 @@ static size_t read_encoded_part_content(curl_mimepart *part,
         if(ateof)
           return cursize;
         break;
-      case CURL_READFUNC_ABORT:
-      case CURL_READFUNC_PAUSE:
       case READ_ERROR:
+      case STOP_FILLING:
         return cursize? cursize: sz;
       default:
         cursize += sz;
@@ -787,7 +876,7 @@ static size_t read_encoded_part_content(curl_mimepart *part,
     if(st->bufend >= sizeof(st->buf))
       return cursize? cursize: READ_ERROR;    /* Buffer full. */
     sz = read_part_content(part, st->buf + st->bufend,
-                           sizeof(st->buf) - st->bufend);
+                           sizeof(st->buf) - st->bufend, hasread);
     switch(sz) {
     case 0:
       ateof = TRUE;
@@ -795,6 +884,7 @@ static size_t read_encoded_part_content(curl_mimepart *part,
     case CURL_READFUNC_ABORT:
     case CURL_READFUNC_PAUSE:
     case READ_ERROR:
+    case STOP_FILLING:
       return cursize? cursize: sz;
     default:
       st->bufend += sz;
@@ -802,12 +892,12 @@ static size_t read_encoded_part_content(curl_mimepart *part,
     }
   }
 
-  return cursize;
+  /* NOTREACHED */
 }
 
 /* Readback a mime part. */
 static size_t readback_part(curl_mimepart *part,
-                            char *buffer, size_t bufsize)
+                            char *buffer, size_t bufsize, bool *hasread)
 {
   size_t cursize = 0;
 #ifdef CURL_DOES_CONVERSIONS
@@ -866,9 +956,9 @@ static size_t readback_part(curl_mimepart *part,
       break;
     case MIMESTATE_CONTENT:
       if(part->encoder)
-        sz = read_encoded_part_content(part, buffer, bufsize);
+        sz = read_encoded_part_content(part, buffer, bufsize, hasread);
       else
-        sz = read_part_content(part, buffer, bufsize);
+        sz = read_part_content(part, buffer, bufsize, hasread);
       switch(sz) {
       case 0:
         mimesetstate(&part->state, MIMESTATE_END, NULL);
@@ -881,6 +971,7 @@ static size_t readback_part(curl_mimepart *part,
       case CURL_READFUNC_ABORT:
       case CURL_READFUNC_PAUSE:
       case READ_ERROR:
+      case STOP_FILLING:
         return cursize? cursize: sz;
       }
       break;
@@ -909,9 +1000,9 @@ static size_t readback_part(curl_mimepart *part,
   return cursize;
 }
 
-/* Readback from mime. */
+/* Readback from mime. Warning: not a read callback function. */
 static size_t mime_subparts_read(char *buffer, size_t size, size_t nitems,
-                                 void *instream)
+                                 void *instream, bool *hasread)
 {
   curl_mime *mime = (curl_mime *) instream;
   size_t cursize = 0;
@@ -932,7 +1023,7 @@ static size_t mime_subparts_read(char *buffer, size_t size, size_t nitems,
 #endif
       mimesetstate(&mime->state, MIMESTATE_BOUNDARY1, mime->firstpart);
       /* The first boundary always follows the header termination empty line,
-         so is always preceded by a CRLK. We can then spare 2 characters
+         so is always preceded by a CRLF. We can then spare 2 characters
          by skipping the leading CRLF in boundary. */
       mime->state.offset += 2;
       break;
@@ -962,11 +1053,12 @@ static size_t mime_subparts_read(char *buffer, size_t size, size_t nitems,
         mimesetstate(&mime->state, MIMESTATE_END, NULL);
         break;
       }
-      sz = readback_part(part, buffer, nitems);
+      sz = readback_part(part, buffer, nitems, hasread);
       switch(sz) {
       case CURL_READFUNC_ABORT:
       case CURL_READFUNC_PAUSE:
       case READ_ERROR:
+      case STOP_FILLING:
         return cursize? cursize: sz;
       case 0:
 #ifdef CURL_DOES_CONVERSIONS
@@ -1031,6 +1123,7 @@ static int mime_part_rewind(curl_mimepart *part)
   if(res == CURL_SEEKFUNC_OK)
     mimesetstate(&part->state, targetstate, NULL);
 
+  part->lastreadstatus = 1; /* Successful read status. */
   return res;
 }
 
@@ -1073,6 +1166,8 @@ static void cleanup_part_content(curl_mimepart *part)
   part->datasize = (curl_off_t) 0;    /* No size yet. */
   cleanup_encoder_state(&part->encstate);
   part->kind = MIMEKIND_NONE;
+  part->flags &= ~MIME_FAST_READ;
+  part->lastreadstatus = 1; /* Successful read status. */
 }
 
 static void mime_subparts_free(void *ptr)
@@ -1238,6 +1333,7 @@ void Curl_mime_initpart(curl_mimepart *part, struct Curl_easy *easy)
 {
   memset((char *) part, 0, sizeof(*part));
   part->easy = easy;
+  part->lastreadstatus = 1; /* Successful read status. */
   mimesetstate(&part->state, MIMESTATE_BEGIN, NULL);
 }
 
@@ -1328,6 +1424,7 @@ CURLcode curl_mime_data(curl_mimepart *part,
     part->readfunc = mime_mem_read;
     part->seekfunc = mime_mem_seek;
     part->freefunc = mime_mem_free;
+    part->flags |= MIME_FAST_READ;
     part->kind = MIMEKIND_DATA;
   }
 
@@ -1405,7 +1502,7 @@ CURLcode curl_mime_type(curl_mimepart *part, const char *mimetype)
 CURLcode curl_mime_encoder(curl_mimepart *part, const char *encoding)
 {
   CURLcode result = CURLE_BAD_FUNCTION_ARGUMENT;
-  const mime_encoder *mep;
+  const struct mime_encoder *mep;
 
   if(!part)
     return result;
@@ -1502,7 +1599,7 @@ CURLcode Curl_mime_set_subparts(curl_mimepart *part,
     }
 
     subparts->parent = part;
-    part->readfunc = mime_subparts_read;
+    /* Subparts are processed internally: no read callback. */
     part->seekfunc = mime_subparts_seek;
     part->freefunc = take_ownership? mime_subparts_free: mime_subparts_unbind;
     part->arg = subparts;
@@ -1524,9 +1621,23 @@ CURLcode curl_mime_subparts(curl_mimepart *part, curl_mime *subparts)
 size_t Curl_mime_read(char *buffer, size_t size, size_t nitems, void *instream)
 {
   curl_mimepart *part = (curl_mimepart *) instream;
+  size_t ret;
+  bool hasread;
 
   (void) size;   /* Always 1. */
-  return readback_part(part, buffer, nitems);
+
+  do {
+    hasread = FALSE;
+    ret = readback_part(part, buffer, nitems, &hasread);
+    /*
+     * If this is not possible to get some data without calling more than
+     * one read callback (probably because a content encoder is not able to
+     * deliver a new bunch for the few data accumulated so far), force another
+     * read until we get enough data or a special exit code.
+     */
+  } while(ret == STOP_FILLING);
+
+  return ret;
 }
 
 /* Rewind mime stream. */
@@ -1667,6 +1778,23 @@ const char *Curl_mime_contenttype(const char *filename)
   return NULL;
 }
 
+static bool content_type_match(const char *contenttype, const char *target)
+{
+  size_t len = strlen(target);
+
+  if(contenttype && strncasecompare(contenttype, target, len))
+    switch(contenttype[len]) {
+    case '\0':
+    case '\t':
+    case '\r':
+    case '\n':
+    case ' ':
+    case ';':
+      return TRUE;
+    }
+  return FALSE;
+}
+
 CURLcode Curl_mime_prepare_headers(curl_mimepart *part,
                                    const char *contenttype,
                                    const char *disposition,
@@ -1718,7 +1846,7 @@ CURLcode Curl_mime_prepare_headers(curl_mimepart *part,
       boundary = mime->boundary;
   }
   else if(contenttype && !customct &&
-          strcasecompare(contenttype, "text/plain"))
+          content_type_match(contenttype, "text/plain"))
     if(strategy == MIMESTRATEGY_MAIL || !part->filename)
       contenttype = NULL;
 
@@ -1794,7 +1922,7 @@ CURLcode Curl_mime_prepare_headers(curl_mimepart *part,
     curl_mimepart *subpart;
 
     disposition = NULL;
-    if(strcasecompare(contenttype, "multipart/form-data"))
+    if(content_type_match(contenttype, "multipart/form-data"))
       disposition = "form-data";
     for(subpart = mime->firstpart; subpart; subpart = subpart->nextpart) {
       ret = Curl_mime_prepare_headers(subpart, NULL, disposition, strategy);
@@ -1805,6 +1933,26 @@ CURLcode Curl_mime_prepare_headers(curl_mimepart *part,
   return ret;
 }
 
+/* Recursively reset paused status in the given part. */
+void Curl_mime_unpause(curl_mimepart *part)
+{
+  if(part) {
+    if(part->lastreadstatus == CURL_READFUNC_PAUSE)
+      part->lastreadstatus = 1; /* Successful read status. */
+    if(part->kind == MIMEKIND_MULTIPART) {
+      curl_mime *mime = (curl_mime *) part->arg;
+
+      if(mime) {
+        curl_mimepart *subpart;
+
+        for(subpart = mime->firstpart; subpart; subpart = subpart->nextpart)
+          Curl_mime_unpause(subpart);
+      }
+    }
+  }
+}
+
+
 #else /* !CURL_DISABLE_HTTP || !CURL_DISABLE_SMTP || !CURL_DISABLE_IMAP */
 
 /* Mime not compiled in: define stubs for externally-referenced functions. */