Extend the tab with 8 whitespace

This work was done as follows:
- check:   `git grep $'\011' -- :^oss-fuzz`
- convert: `ruby -pi -e 'nil while $_.sub!(/^(.*?)\t/) { $1 + " " * (8 - $1.size % 8) }'`

The `doc/guide/{compile,mrbgems}.md` file adds and removes whitespace to make the directory tree look the same.
In `mrbgems/mruby-socket/src/socket.c`, there is a part where the indent is changed from 4 to 2 at the same time as the tab is changed.

5 files changed, 190 insertions, 180 deletions

diff --git a/doc/guides/compile.md b/doc/guides/compile.md
index 7156b2b68..08dbd850f 100644
--- a/doc/guides/compile.md
+++ b/doc/guides/compile.md
@@ -333,9 +333,9 @@ conf.enable_debug
 When debugging mode is enabled
 
 * Macro `MRB_DEBUG` would be defined.
-	* Which means `mrb_assert()` macro is enabled.
+  * Which means `mrb_assert()` macro is enabled.
 * Debug information of irep would be generated by `mrbc`.
-	* Because `-g` flag would be added to `mrbc` runner.
+  * Because `-g` flag would be added to `mrbc` runner.
     * You can have better backtrace of mruby scripts with this.
 
 ## Cross-Compilation
@@ -379,23 +379,25 @@ end
 During the build process the directory `build` will be created in the
 root directory. The structure of this directory will look like this:
 
-	+- build
-	   |
-	   +-  host
-	       |
-	       +- LEGAL        <- License description
-	       |
-	       +- bin          <- Binaries (mirb, mrbc and mruby)
-	       |
-	       +- lib          <- Libraries (libmruby.a and libmruby_core.a)
-	       |
-	       +- mrbc         <- Minimal mrbc place
-	       |
-	       +- mrbgems      <- Compilation result from mrbgems
-	       |
-	       +- mrblib       <- Compilation result from mrblib
-	       |
-	       +- src          <- Compilation result from C sources
+```
++- build
+    |
+    +- host
+        |
+        +- LEGAL        <- License description
+        |
+        +- bin          <- Binaries (mirb, mrbc and mruby)
+        |
+        +- lib          <- Libraries (libmruby.a and libmruby_core.a)
+        |
+        +- mrbc         <- Minimal mrbc place
+        |
+        +- mrbgems      <- Compilation result from mrbgems
+        |
+        +- mrblib       <- Compilation result from mrblib
+        |
+        +- src          <- Compilation result from C sources
+```
 
 The compilation workflow will look like this:
 
@@ -425,31 +427,33 @@ The compilation workflow will look like this:
 In case of a cross-compilation to `i386` the `build` directory structure looks
 like this:
 
-	+- build
-	   |
-	   +-  host
-	   |   |
-	   |   +- bin           <- Native Binaries
-	   |   |
-	   |   +- lib           <- Native Libraries
-	   |   |
-	   |   +- mrbgems
-	   |   |
-	   |   +- src
-       |
-	   +- i386
-	      |
-	      +- bin            <- Cross-compiled Binaries
-	      |
-	      +- include        <- Header Directory
-	      |
-	      +- lib            <- Cross-compiled Libraries
-	      |
-	      +- mrbgems
-	      |
-	      +- mrblib
-	      |
-	      +- src
+```
++- build
+    |
+    +- host
+    |   |
+    |   +- bin           <- Native Binaries
+    |   |
+    |   +- lib           <- Native Libraries
+    |   |
+    |   +- mrbgems
+    |   |
+    |   +- src
+    |
+    +- i386
+        |
+        +- bin            <- Cross-compiled Binaries
+        |
+        +- include        <- Header Directory
+        |
+        +- lib            <- Cross-compiled Libraries
+        |
+        +- mrbgems
+        |
+        +- mrblib
+        |
+        +- src
+```
 
 An extra directory is created for the target platform. In case you
 compile for `i386` a directory called `i386` is created under the
diff --git a/doc/guides/mrbgems.md b/doc/guides/mrbgems.md
index d4160ebc8..9aebb9208 100644
--- a/doc/guides/mrbgems.md
+++ b/doc/guides/mrbgems.md
@@ -111,21 +111,21 @@ contains every gem found in the `mrbgems` directory.
 The maximal GEM structure looks like this:
 
 ```
-+- GEM_NAME         <- Name of GEM
-   |
-   +- README.md     <- Readme for GEM
-   |
-   +- mrbgem.rake   <- GEM Specification
-   |
-   +- include/      <- Header for Ruby extension (will exported)
-   |
-   +- mrblib/       <- Source for Ruby extension
-   |
-   +- src/          <- Source for C extension
-   |
-   +- tools/        <- Source for Executable (in C)
-   |
-   +- test/         <- Test code (Ruby)
++- GEM_NAME             <- Name of GEM
+    |
+    +- README.md        <- Readme for GEM
+    |
+    +- mrbgem.rake      <- GEM Specification
+    |
+    +- include/         <- Header for Ruby extension (will exported)
+    |
+    +- mrblib/          <- Source for Ruby extension
+    |
+    +- src/             <- Source for C extension
+    |
+    +- tools/           <- Source for Executable (in C)
+    |
+    +- test/            <- Test code (Ruby)
 ```
 
 The folder `mrblib` contains pure Ruby files to extend mruby. The folder `src`
@@ -297,19 +297,21 @@ mrb_c_extension_example_gem_final(mrb_state* mrb) {
 
 ### Example
 
-	+- c_extension_example/
-	   |
-	   +- README.md         (Optional)
-	   |
-	   +- src/
-	   |  |
-	   |  +- example.c         <- C extension source
-	   |
-	   +- test/
-	   |  |
-	   |  +- example.rb        <- Test code for C extension
-	   |
-	   +- mrbgem.rake          <- GEM specification
+```
++- c_extension_example/
+    |
+    +- README.md        (Optional)
+    |
+    +- src/
+    |   |
+    |   +- example.c    <- C extension source
+    |
+    +- test/
+    |   |
+    |   +- example.rb   <- Test code for C extension
+    |
+    +- mrbgem.rake      <- GEM specification
+```
 
 ## Ruby Extension
 
@@ -323,19 +325,21 @@ none
 
 ### Example
 
-	+- ruby_extension_example/
-	   |
-	   +- README.md         (Optional)
-	   |
-	   +- mrblib/
-	   |  |
-	   |  +- example.rb     <- Ruby extension source
-	   |
-	   +- test/
-	   |  |
-	   |  +- example.rb     <- Test code for Ruby extension
-	   |
-	   +- mrbgem.rake       <- GEM specification
+```
++- ruby_extension_example/
+    |
+    +- README.md        (Optional)
+    |
+    +- mrblib/
+    |   |
+    |   +- example.rb   <- Ruby extension source
+    |
+    +- test/
+    |   |
+    |   +- example.rb   <- Test code for Ruby extension
+    |
+    +- mrbgem.rake      <- GEM specification
+```
 
 ## C and Ruby Extension
 
@@ -353,23 +357,25 @@ See C and Ruby example.
 
 ### Example
 
-	+- c_and_ruby_extension_example/
-	   |
-	   +- README.md         (Optional)
-	   |
-	   +- mrblib/
-	   |  |
-	   |  +- example.rb     <- Ruby extension source
-	   |
-	   +- src/
-	   |  |
-	   |  +- example.c      <- C extension source
-	   |
-	   +- test/
-	   |  |
-	   |  +- example.rb     <- Test code for C and Ruby extension
-	   |
-	   +- mrbgem.rake       <- GEM specification
+```
++- c_and_ruby_extension_example/
+    |
+    +- README.md        (Optional)
+    |
+    +- mrblib/
+    |   |
+    |   +- example.rb   <- Ruby extension source
+    |
+    +- src/
+    |   |
+    |   +- example.c    <- C extension source
+    |
+    +- test/
+    |   |
+    |   +- example.rb   <- Test code for C and Ruby extension
+    |
+    +- mrbgem.rake      <- GEM specification
+```
 
 ## Binary gems
 
@@ -389,23 +395,23 @@ binary gems, to separate normal gems and binary gems.
 ### Example
 
 ```
- +- mruby-bin-example/
++- mruby-bin-example/
     |
-    +- README.md         (Optional)
+    +- README.md        (Optional)
     |
     +- bintest/
-    |  |
-    |  +- example.rb     <- Test code for binary gem
+    |   |
+    |   +- example.rb   <- Test code for binary gem
     |
-    +- mrbgem.rake       <- Gem specification
+    +- mrbgem.rake      <- Gem specification
     |
-    +- mrblib/           <- Source for Ruby extension (Optional)
+    +- mrblib/          <- Source for Ruby extension (Optional)
     |
-    +- src/              <- Source for C extension (Optional)
+    +- src/             <- Source for C extension (Optional)
     |
     +- tools/
-       |
-       +- example/       <- Executable name directory
-       |
-       +- example.c	 <- Source for Executable (includes main)
+        |
+        +- example/     <- Executable name directory
+        |
+        +- example.c    <- Source for Executable (includes main)
 ```
diff --git a/mrbgems/mruby-pack/src/pack.c b/mrbgems/mruby-pack/src/pack.c
index e52171d6b..9b462b1b8 100644
--- a/mrbgems/mruby-pack/src/pack.c
+++ b/mrbgems/mruby-pack/src/pack.c
@@ -48,19 +48,19 @@ enum {
   PACK_TYPE_NONE
 };
 
-#define PACK_FLAG_s             0x00000001	/* native size ("_" "!") */
-#define PACK_FLAG_a             0x00000002	/* null padding ("a") */
-#define PACK_FLAG_Z             0x00000004	/* append nul char ("z") */
-#define PACK_FLAG_SIGNED        0x00000008	/* native size ("_" "!") */
-#define PACK_FLAG_GT            0x00000010	/* big endian (">") */
-#define PACK_FLAG_LT            0x00000020	/* little endian ("<") */
-#define PACK_FLAG_WIDTH         0x00000040	/* "count" is "width" */
-#define PACK_FLAG_LSB           0x00000080	/* LSB / low nibble first */
-#define PACK_FLAG_COUNT2        0x00000100	/* "count" is special... */
-#define PACK_FLAG_LITTLEENDIAN  0x00000200	/* little endian actually */
-
-#define PACK_BASE64_IGNORE	0xff
-#define PACK_BASE64_PADDING	0xfe
+#define PACK_FLAG_s             0x00000001      /* native size ("_" "!") */
+#define PACK_FLAG_a             0x00000002      /* null padding ("a") */
+#define PACK_FLAG_Z             0x00000004      /* append nul char ("z") */
+#define PACK_FLAG_SIGNED        0x00000008      /* native size ("_" "!") */
+#define PACK_FLAG_GT            0x00000010      /* big endian (">") */
+#define PACK_FLAG_LT            0x00000020      /* little endian ("<") */
+#define PACK_FLAG_WIDTH         0x00000040      /* "count" is "width" */
+#define PACK_FLAG_LSB           0x00000080      /* LSB / low nibble first */
+#define PACK_FLAG_COUNT2        0x00000100      /* "count" is special... */
+#define PACK_FLAG_LITTLEENDIAN  0x00000200      /* little endian actually */
+
+#define PACK_BASE64_IGNORE      0xff
+#define PACK_BASE64_PADDING     0xfe
 
 const static unsigned char base64chars[] =
     "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
@@ -874,13 +874,13 @@ unpack_m(mrb_state *mrb, const void *src, int slen, mrb_value ary, unsigned int
         if (slen-- == 0)
           goto done;
         c = *sptr++;
-	if (c >= sizeof(base64_dec_tab))
-	  continue;
-	ch[i] = base64_dec_tab[c];
-	if (ch[i] == PACK_BASE64_PADDING) {
-	  ch[i] = 0;
-	  padding++;
-	}
+        if (c >= sizeof(base64_dec_tab))
+          continue;
+        ch[i] = base64_dec_tab[c];
+        if (ch[i] == PACK_BASE64_PADDING) {
+          ch[i] = 0;
+          padding++;
+        }
       } while (c >= sizeof(base64_dec_tab) || ch[i] == PACK_BASE64_IGNORE);
     }
 
diff --git a/mrbgems/mruby-socket/src/socket.c b/mrbgems/mruby-socket/src/socket.c
index 28418fa12..82d3a1109 100644
--- a/mrbgems/mruby-socket/src/socket.c
+++ b/mrbgems/mruby-socket/src/socket.c
@@ -65,52 +65,52 @@
 #ifdef _WIN32
 static const char *inet_ntop(int af, const void *src, char *dst, socklen_t cnt)
 {
-    if (af == AF_INET)
-    {
-	struct sockaddr_in in;
-	memset(&in, 0, sizeof(in));
-	in.sin_family = AF_INET;
-	memcpy(&in.sin_addr, src, sizeof(struct in_addr));
-	getnameinfo((struct sockaddr *)&in, sizeof(struct
-		    sockaddr_in), dst, cnt, NULL, 0, NI_NUMERICHOST);
-	return dst;
-    }
-    else if (af == AF_INET6)
-    {
-	struct sockaddr_in6 in;
-	memset(&in, 0, sizeof(in));
-	in.sin6_family = AF_INET6;
-	memcpy(&in.sin6_addr, src, sizeof(struct in_addr6));
-	getnameinfo((struct sockaddr *)&in, sizeof(struct
-		    sockaddr_in6), dst, cnt, NULL, 0, NI_NUMERICHOST);
-	return dst;
-    }
-    return NULL;
+  if (af == AF_INET)
+  {
+    struct sockaddr_in in;
+    memset(&in, 0, sizeof(in));
+    in.sin_family = AF_INET;
+    memcpy(&in.sin_addr, src, sizeof(struct in_addr));
+    getnameinfo((struct sockaddr *)&in, sizeof(struct
+                sockaddr_in), dst, cnt, NULL, 0, NI_NUMERICHOST);
+    return dst;
+  }
+  else if (af == AF_INET6)
+  {
+    struct sockaddr_in6 in;
+    memset(&in, 0, sizeof(in));
+    in.sin6_family = AF_INET6;
+    memcpy(&in.sin6_addr, src, sizeof(struct in_addr6));
+    getnameinfo((struct sockaddr *)&in, sizeof(struct
+                sockaddr_in6), dst, cnt, NULL, 0, NI_NUMERICHOST);
+    return dst;
+  }
+  return NULL;
 }
 
 static int inet_pton(int af, const char *src, void *dst)
 {
-    struct addrinfo hints, *res, *ressave;
+  struct addrinfo hints, *res, *ressave;
 
-    memset(&hints, 0, sizeof(struct addrinfo));
-    hints.ai_family = af;
+  memset(&hints, 0, sizeof(struct addrinfo));
+  hints.ai_family = af;
 
-    if (getaddrinfo(src, NULL, &hints, &res) != 0)
-    {
-	printf("Couldn't resolve host %s\n", src);
-	return -1;
-    }
+  if (getaddrinfo(src, NULL, &hints, &res) != 0)
+  {
+    printf("Couldn't resolve host %s\n", src);
+    return -1;
+  }
 
-    ressave = res;
+  ressave = res;
 
-    while (res)
-    {
-	memcpy(dst, res->ai_addr, res->ai_addrlen);
-	res = res->ai_next;
-    }
+  while (res)
+  {
+    memcpy(dst, res->ai_addr, res->ai_addrlen);
+    res = res->ai_next;
+  }
 
-    freeaddrinfo(ressave);
-    return 0;
+  freeaddrinfo(ressave);
+  return 0;
 }
 
 #endif
@@ -574,7 +574,7 @@ mrb_ipsocket_recvfrom(mrb_state *mrb, mrb_value self)
   buf = mrb_str_new_capa(mrb, maxlen);
   socklen = sizeof(ss);
   n = recvfrom(fd, RSTRING_PTR(buf), (fsize_t)maxlen, (int)flags,
-  	       (struct sockaddr *)&ss, &socklen);
+               (struct sockaddr *)&ss, &socklen);
   if (n == -1) {
     mrb_sys_fail(mrb, "recvfrom");
   }
@@ -938,8 +938,8 @@ mrb_mruby_socket_gem_init(mrb_state* mrb)
   constants = mrb_define_module_under(mrb, sock, "Constants");
 
 #define define_const(SYM) \
-  do {								\
-    mrb_define_const(mrb, constants, #SYM, mrb_int_value(mrb, SYM));	\
+  do {                                                                \
+    mrb_define_const(mrb, constants, #SYM, mrb_int_value(mrb, SYM));  \
   } while (0)
 
 #include "const.cstub"
diff --git a/mrbgems/mruby-string-ext/src/string.c b/mrbgems/mruby-string-ext/src/string.c
index 09cbf7995..3a9926525 100644
--- a/mrbgems/mruby-string-ext/src/string.c
+++ b/mrbgems/mruby-string-ext/src/string.c
@@ -262,7 +262,7 @@ enum tr_pattern_type {
   <range> ::= <ch> '-' <ch>
 */
 struct tr_pattern {
-  uint8_t type;		// 1:in-order, 2:range
+  uint8_t type;                 // 1:in-order, 2:range
   mrb_bool flag_reverse : 1;
   mrb_bool flag_on_heap : 1;
   uint16_t n;
@@ -329,9 +329,9 @@ tr_parse_pattern(mrb_state *mrb, struct tr_pattern *ret, const mrb_value v_patte
       mrb_int len;
 
       while (i < pattern_length) {
-	if ((i+2) < pattern_length && pattern[i] != '\\' && pattern[i+1] == '-')
+        if ((i+2) < pattern_length && pattern[i] != '\\' && pattern[i+1] == '-')
           break;
-	i++;
+        i++;
       }
 
       len = i - start_pos;
@@ -375,7 +375,7 @@ tr_find_character(const struct tr_pattern *pat, const char *pat_str, int ch)
     if (pat->type == TR_IN_ORDER) {
       int i;
       for (i = 0; i < pat->n; i++) {
-	if (pat_str[pat->val.start_pos + i] == ch) ret = n_sum + i;
+        if (pat_str[pat->val.start_pos + i] == ch) ret = n_sum + i;
       }
     }
     else if (pat->type == TR_RANGE) {
@@ -509,7 +509,7 @@ str_tr(mrb_state *mrb, mrb_value str, mrb_value p1, mrb_value p2, mrb_bool squee
     if (n >= 0) {
       flag_changed = TRUE;
       if (rep == NULL) {
-	j--;
+        j--;
       }
       else {
         mrb_int c = tr_get_character(rep, RSTRING_PTR(p2), n);
@@ -521,8 +521,8 @@ str_tr(mrb_state *mrb, mrb_value str, mrb_value p1, mrb_value p2, mrb_bool squee
         if (c > 0x80) {
           mrb_raisef(mrb, E_ARGUMENT_ERROR, "character (%i) out of range", c);
         }
-	lastch = c;
-	s[i] = (char)c;
+        lastch = c;
+        s[i] = (char)c;
       }
     }
   }