Revert changes relative to lib/*.[ch] recent renaming

This reverts renaming and usage of lib/*.h header files done
28-12-2012, reverting 2 commits:

  f871de0... build: make use of 76 lib/*.h renamed files
  ffd8e12... build: rename 76 lib/*.h files

This also reverts removal of redundant include guard (redundant thanks
to changes in above commits) done 2-12-2013, reverting 1 commit:

  c087374... curl_setup.h: remove redundant include guard

This also reverts renaming and usage of lib/*.c source files done
3-12-2013, reverting 3 commits:

  13606bb... build: make use of 93 lib/*.c renamed files
  5b6e792... build: rename 93 lib/*.c files
  7d83dff... build: commit 13606bbfde follow-up 1

Start of related discussion thread:

  http://curl.haxx.se/mail/lib-2013-01/0012.html

Asking for confirmation on pushing this revertion commit:

  http://curl.haxx.se/mail/lib-2013-01/0048.html

Confirmation summary:

  http://curl.haxx.se/mail/lib-2013-01/0079.html

NOTICE: The list of 2 files that have been modified by other
intermixed commits, while renamed, and also by at least one
of the 6 commits this one reverts follows below. These 2 files
will exhibit a hole in history unless git's '--follow' option
is used when viewing logs.

  lib/curl_imap.h
  lib/curl_smtp.h

1 files changed, 435 insertions, 0 deletions

diff --git a/lib/content_encoding.c b/lib/content_encoding.c
new file mode 100644
index 000000000..3276ef988
--- /dev/null
+++ b/lib/content_encoding.c
@@ -0,0 +1,435 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2011, 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 http://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 "setup.h"
+
+#ifdef HAVE_LIBZ
+
+#include "urldata.h"
+#include <curl/curl.h>
+#include "sendf.h"
+#include "content_encoding.h"
+#include "curl_memory.h"
+
+#include "memdebug.h"
+
+/* Comment this out if zlib is always going to be at least ver. 1.2.0.4
+   (doing so will reduce code size slightly). */
+#define OLD_ZLIB_SUPPORT 1
+
+#define DSIZ CURL_MAX_WRITE_SIZE /* buffer size for decompressed data */
+
+#define GZIP_MAGIC_0 0x1f
+#define GZIP_MAGIC_1 0x8b
+
+/* gzip flag byte */
+#define ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
+#define HEAD_CRC     0x02 /* bit 1 set: header CRC present */
+#define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
+#define ORIG_NAME    0x08 /* bit 3 set: original file name present */
+#define COMMENT      0x10 /* bit 4 set: file comment present */
+#define RESERVED     0xE0 /* bits 5..7: reserved */
+
+static voidpf
+zalloc_cb(voidpf opaque, unsigned int items, unsigned int size)
+{
+  (void) opaque;
+  /* not a typo, keep it calloc() */
+  return (voidpf) calloc(items, size);
+}
+
+static void
+zfree_cb(voidpf opaque, voidpf ptr)
+{
+  (void) opaque;
+  free(ptr);
+}
+
+static CURLcode
+process_zlib_error(struct connectdata *conn, z_stream *z)
+{
+  struct SessionHandle *data = conn->data;
+  if(z->msg)
+    failf (data, "Error while processing content unencoding: %s",
+           z->msg);
+  else
+    failf (data, "Error while processing content unencoding: "
+           "Unknown failure within decompression software.");
+
+  return CURLE_BAD_CONTENT_ENCODING;
+}
+
+static CURLcode
+exit_zlib(z_stream *z, zlibInitState *zlib_init, CURLcode result)
+{
+  inflateEnd(z);
+  *zlib_init = ZLIB_UNINIT;
+  return result;
+}
+
+static CURLcode
+inflate_stream(struct connectdata *conn,
+               struct SingleRequest *k)
+{
+  int allow_restart = 1;
+  z_stream *z = &k->z;          /* zlib state structure */
+  uInt nread = z->avail_in;
+  Bytef *orig_in = z->next_in;
+  int status;                   /* zlib status */
+  CURLcode result = CURLE_OK;   /* Curl_client_write status */
+  char *decomp;                 /* Put the decompressed data here. */
+
+  /* Dynamically allocate a buffer for decompression because it's uncommonly
+     large to hold on the stack */
+  decomp = malloc(DSIZ);
+  if(decomp == NULL) {
+    return exit_zlib(z, &k->zlib_init, CURLE_OUT_OF_MEMORY);
+  }
+
+  /* because the buffer size is fixed, iteratively decompress and transfer to
+     the client via client_write. */
+  for(;;) {
+    /* (re)set buffer for decompressed output for every iteration */
+    z->next_out = (Bytef *)decomp;
+    z->avail_out = DSIZ;
+
+    status = inflate(z, Z_SYNC_FLUSH);
+    if(status == Z_OK || status == Z_STREAM_END) {
+      allow_restart = 0;
+      if((DSIZ - z->avail_out) && (!k->ignorebody)) {
+        result = Curl_client_write(conn, CLIENTWRITE_BODY, decomp,
+                                   DSIZ - z->avail_out);
+        /* if !CURLE_OK, clean up, return */
+        if(result) {
+          free(decomp);
+          return exit_zlib(z, &k->zlib_init, result);
+        }
+      }
+
+      /* Done? clean up, return */
+      if(status == Z_STREAM_END) {
+        free(decomp);
+        if(inflateEnd(z) == Z_OK)
+          return exit_zlib(z, &k->zlib_init, result);
+        else
+          return exit_zlib(z, &k->zlib_init, process_zlib_error(conn, z));
+      }
+
+      /* Done with these bytes, exit */
+
+      /* status is always Z_OK at this point! */
+      if(z->avail_in == 0) {
+        free(decomp);
+        return result;
+      }
+    }
+    else if(allow_restart && status == Z_DATA_ERROR) {
+      /* some servers seem to not generate zlib headers, so this is an attempt
+         to fix and continue anyway */
+
+      (void) inflateEnd(z);     /* don't care about the return code */
+      if(inflateInit2(z, -MAX_WBITS) != Z_OK) {
+        free(decomp);
+        return exit_zlib(z, &k->zlib_init, process_zlib_error(conn, z));
+      }
+      z->next_in = orig_in;
+      z->avail_in = nread;
+      allow_restart = 0;
+      continue;
+    }
+    else {                      /* Error; exit loop, handle below */
+      free(decomp);
+      return exit_zlib(z, &k->zlib_init, process_zlib_error(conn, z));
+    }
+  }
+  /* Will never get here */
+}
+
+CURLcode
+Curl_unencode_deflate_write(struct connectdata *conn,
+                            struct SingleRequest *k,
+                            ssize_t nread)
+{
+  z_stream *z = &k->z;          /* zlib state structure */
+
+  /* Initialize zlib? */
+  if(k->zlib_init == ZLIB_UNINIT) {
+    memset(z, 0, sizeof(z_stream));
+    z->zalloc = (alloc_func)zalloc_cb;
+    z->zfree = (free_func)zfree_cb;
+
+    if(inflateInit(z) != Z_OK)
+      return process_zlib_error(conn, z);
+    k->zlib_init = ZLIB_INIT;
+  }
+
+  /* Set the compressed input when this function is called */
+  z->next_in = (Bytef *)k->str;
+  z->avail_in = (uInt)nread;
+
+  /* Now uncompress the data */
+  return inflate_stream(conn, k);
+}
+
+#ifdef OLD_ZLIB_SUPPORT
+/* Skip over the gzip header */
+static enum {
+  GZIP_OK,
+  GZIP_BAD,
+  GZIP_UNDERFLOW
+} check_gzip_header(unsigned char const *data, ssize_t len, ssize_t *headerlen)
+{
+  int method, flags;
+  const ssize_t totallen = len;
+
+  /* The shortest header is 10 bytes */
+  if(len < 10)
+    return GZIP_UNDERFLOW;
+
+  if((data[0] != GZIP_MAGIC_0) || (data[1] != GZIP_MAGIC_1))
+    return GZIP_BAD;
+
+  method = data[2];
+  flags = data[3];
+
+  if(method != Z_DEFLATED || (flags & RESERVED) != 0) {
+    /* Can't handle this compression method or unknown flag */
+    return GZIP_BAD;
+  }
+
+  /* Skip over time, xflags, OS code and all previous bytes */
+  len -= 10;
+  data += 10;
+
+  if(flags & EXTRA_FIELD) {
+    ssize_t extra_len;
+
+    if(len < 2)
+      return GZIP_UNDERFLOW;
+
+    extra_len = (data[1] << 8) | data[0];
+
+    if(len < (extra_len+2))
+      return GZIP_UNDERFLOW;
+
+    len -= (extra_len + 2);
+    data += (extra_len + 2);
+  }
+
+  if(flags & ORIG_NAME) {
+    /* Skip over NUL-terminated file name */
+    while(len && *data) {
+      --len;
+      ++data;
+    }
+    if(!len || *data)
+      return GZIP_UNDERFLOW;
+
+    /* Skip over the NUL */
+    --len;
+    ++data;
+  }
+
+  if(flags & COMMENT) {
+    /* Skip over NUL-terminated comment */
+    while(len && *data) {
+      --len;
+      ++data;
+    }
+    if(!len || *data)
+      return GZIP_UNDERFLOW;
+
+    /* Skip over the NUL */
+    --len;
+  }
+
+  if(flags & HEAD_CRC) {
+    if(len < 2)
+      return GZIP_UNDERFLOW;
+
+    len -= 2;
+  }
+
+  *headerlen = totallen - len;
+  return GZIP_OK;
+}
+#endif
+
+CURLcode
+Curl_unencode_gzip_write(struct connectdata *conn,
+                         struct SingleRequest *k,
+                         ssize_t nread)
+{
+  z_stream *z = &k->z;          /* zlib state structure */
+
+  /* Initialize zlib? */
+  if(k->zlib_init == ZLIB_UNINIT) {
+    memset(z, 0, sizeof(z_stream));
+    z->zalloc = (alloc_func)zalloc_cb;
+    z->zfree = (free_func)zfree_cb;
+
+    if(strcmp(zlibVersion(), "1.2.0.4") >= 0) {
+      /* zlib ver. >= 1.2.0.4 supports transparent gzip decompressing */
+      if(inflateInit2(z, MAX_WBITS+32) != Z_OK) {
+        return process_zlib_error(conn, z);
+      }
+      k->zlib_init = ZLIB_INIT_GZIP; /* Transparent gzip decompress state */
+    }
+    else {
+      /* we must parse the gzip header ourselves */
+      if(inflateInit2(z, -MAX_WBITS) != Z_OK) {
+        return process_zlib_error(conn, z);
+      }
+      k->zlib_init = ZLIB_INIT;   /* Initial call state */
+    }
+  }
+
+  if(k->zlib_init == ZLIB_INIT_GZIP) {
+    /* Let zlib handle the gzip decompression entirely */
+    z->next_in = (Bytef *)k->str;
+    z->avail_in = (uInt)nread;
+    /* Now uncompress the data */
+    return inflate_stream(conn, k);
+  }
+
+#ifndef OLD_ZLIB_SUPPORT
+  /* Support for old zlib versions is compiled away and we are running with
+     an old version, so return an error. */
+  return exit_zlib(z, &k->zlib_init, CURLE_FUNCTION_NOT_FOUND);
+
+#else
+  /* This next mess is to get around the potential case where there isn't
+   * enough data passed in to skip over the gzip header.  If that happens, we
+   * malloc a block and copy what we have then wait for the next call.  If
+   * there still isn't enough (this is definitely a worst-case scenario), we
+   * make the block bigger, copy the next part in and keep waiting.
+   *
+   * This is only required with zlib versions < 1.2.0.4 as newer versions
+   * can handle the gzip header themselves.
+   */
+
+  switch (k->zlib_init) {
+  /* Skip over gzip header? */
+  case ZLIB_INIT:
+  {
+    /* Initial call state */
+    ssize_t hlen;
+
+    switch (check_gzip_header((unsigned char *)k->str, nread, &hlen)) {
+    case GZIP_OK:
+      z->next_in = (Bytef *)k->str + hlen;
+      z->avail_in = (uInt)(nread - hlen);
+      k->zlib_init = ZLIB_GZIP_INFLATING; /* Inflating stream state */
+      break;
+
+    case GZIP_UNDERFLOW:
+      /* We need more data so we can find the end of the gzip header.  It's
+       * possible that the memory block we malloc here will never be freed if
+       * the transfer abruptly aborts after this point.  Since it's unlikely
+       * that circumstances will be right for this code path to be followed in
+       * the first place, and it's even more unlikely for a transfer to fail
+       * immediately afterwards, it should seldom be a problem.
+       */
+      z->avail_in = (uInt)nread;
+      z->next_in = malloc(z->avail_in);
+      if(z->next_in == NULL) {
+        return exit_zlib(z, &k->zlib_init, CURLE_OUT_OF_MEMORY);
+      }
+      memcpy(z->next_in, k->str, z->avail_in);
+      k->zlib_init = ZLIB_GZIP_HEADER;   /* Need more gzip header data state */
+      /* We don't have any data to inflate yet */
+      return CURLE_OK;
+
+    case GZIP_BAD:
+    default:
+      return exit_zlib(z, &k->zlib_init, process_zlib_error(conn, z));
+    }
+
+  }
+  break;
+
+  case ZLIB_GZIP_HEADER:
+  {
+    /* Need more gzip header data state */
+    ssize_t hlen;
+    unsigned char *oldblock = z->next_in;
+
+    z->avail_in += (uInt)nread;
+    z->next_in = realloc(z->next_in, z->avail_in);
+    if(z->next_in == NULL) {
+      free(oldblock);
+      return exit_zlib(z, &k->zlib_init, CURLE_OUT_OF_MEMORY);
+    }
+    /* Append the new block of data to the previous one */
+    memcpy(z->next_in + z->avail_in - nread, k->str, nread);
+
+    switch (check_gzip_header(z->next_in, z->avail_in, &hlen)) {
+    case GZIP_OK:
+      /* This is the zlib stream data */
+      free(z->next_in);
+      /* Don't point into the malloced block since we just freed it */
+      z->next_in = (Bytef *)k->str + hlen + nread - z->avail_in;
+      z->avail_in = (uInt)(z->avail_in - hlen);
+      k->zlib_init = ZLIB_GZIP_INFLATING;   /* Inflating stream state */
+      break;
+
+    case GZIP_UNDERFLOW:
+      /* We still don't have any data to inflate! */
+      return CURLE_OK;
+
+    case GZIP_BAD:
+    default:
+      free(z->next_in);
+      return exit_zlib(z, &k->zlib_init, process_zlib_error(conn, z));
+    }
+
+  }
+  break;
+
+  case ZLIB_GZIP_INFLATING:
+  default:
+    /* Inflating stream state */
+    z->next_in = (Bytef *)k->str;
+    z->avail_in = (uInt)nread;
+    break;
+  }
+
+  if(z->avail_in == 0) {
+    /* We don't have any data to inflate; wait until next time */
+    return CURLE_OK;
+  }
+
+  /* We've parsed the header, now uncompress the data */
+  return inflate_stream(conn, k);
+#endif
+}
+
+void Curl_unencode_cleanup(struct connectdata *conn)
+{
+  struct SessionHandle *data = conn->data;
+  struct SingleRequest *k = &data->req;
+  z_stream *z = &k->z;
+  if(k->zlib_init != ZLIB_UNINIT)
+    (void) exit_zlib(z, &k->zlib_init, CURLE_OK);
+}
+
+#endif /* HAVE_LIBZ */