Merge branch 'ppm' into working

Conflicts:
	stb_image.h

stb_image.h

@@ -1,4 +1,4 @@
-/* stb_image - v1.48 - public domain JPEG/PNG reader - http://nothings.org/stb_image.c
+/* stb_image - v1.49 - public domain JPEG/PNG reader - http://nothings.org/stb_image.c
    when you control the images you're loading
                                      no warranty implied; use at your own risk
 
@@ -24,6 +24,7 @@
       GIF (*comp always reports as 4-channel)
       HDR (radiance rgbE format)
       PIC (Softimage PIC)
+      PNM (PPM and PGM binary only)
 
       - decode from memory or through FILE (define STBI_NO_STDIO to remove code)
       - decode from arbitrary I/O callbacks
@@ -72,12 +73,18 @@
         removed in future versions of the library. It is only intended for
         back-compatibility use.
 
+      - Added support for PNM images.
+
+      - Added STBI_MALLOC, STBI_REALLOC, and STBI_FREE macros for replacing
+        the memory allocator. Unlike other STBI libraries, these macros don't
+        support a context parameter, so if you need to pass a context in to
+        the allocator, you'll have to store it in a global or a thread-local
+        variable.
+
 
    Latest revision history:
       1.49 (2014-12-25) optimize JPG, incl. x86 SIMD
                         PGM/PPM support
-                        allocation macros
-                        stbi_load_into() -- load into pre-defined memory
                         STBI_MALLOC,STBI_REALLOC,STBI_FREE
       1.48 (2014-12-14) fix incorrectly-named assert()
       1.47 (2014-12-14) 1/2/4-bit PNG support (both grayscale and paletted)
@@ -85,10 +92,6 @@
                         fix bug in interlaced PNG with user-specified channel count
       1.46 (2014-08-26) fix broken tRNS chunk in non-paletted PNG
       1.45 (2014-08-16) workaround MSVC-ARM internal compiler error by wrapping malloc
-      1.44 (2014-08-07) warnings
-      1.43 (2014-07-15) fix MSVC-only bug in 1.42
-      1.42 (2014-07-09) no _CRT_SECURE_NO_WARNINGS; error-path fixes; STBI_ASSERT
-      1.41 (2014-06-25) fix search&replace that messed up comments/error messages
 
    See end of file for full revision history.
 
@@ -102,26 +105,34 @@
     Jean-Marc Lienher (gif)                      Won Chun
     Tom Seddon (pic)                             the Horde3D community
     Thatcher Ulrich (psd)                        Janez Zemva
-                                                 Jonathan Blow
+    Ken Miller (pgm, ppm)                        Jonathan Blow
                                                  Laurent Gomila
- Extensions, features                            Aruelien Pocheville
+                                                 Aruelien Pocheville
-    Jetro Lauha (stbi_info)                      Ryamond Barbiero
+ Extensions, features                            Ryamond Barbiero
-    James "moose2000" Brown (iPhone PNG)         David Woo
+    Jetro Lauha (stbi_info)                      David Woo
-    Ben "Disch" Wenger (io callbacks)            Roy Eltham
+    Martin "SpartanJ" Golini (stbi_info)         Martin Golini
-    Martin "SpartanJ" Golini                     Luke Graham
+    James "moose2000" Brown (iPhone PNG)         Roy Eltham
-    Omar Cornut (1/2/4-bit png)                  Thomas Ruf
+    Ben "Disch" Wenger (io callbacks)            Luke Graham
+    Omar Cornut (1/2/4-bit PNG)                  Thomas Ruf
                                                  John Bartholomew
- Optimizations & bugfixes                        Ken Hamada
+                                                 Ken Hamada
-    Fabian "ryg" Giesen                          Cort Stratton
+ Optimizations & bugfixes                        Cort Stratton
-    Arseny Kapoulkine                            Blazej Dariusz Roszkowski
+    Fabian "ryg" Giesen                          Blazej Dariusz Roszkowski
-                                                 Thibault Reuille
+    Arseny Kapoulkine                            Thibault Reuille
                                                  Paul Du Bois
                                                  Guillaume George
-                                                 Jerry Jansson
+  If your name should be here but                Jerry Jansson
-  If your name should be here but                Hayaki Saito
+  isn't, let Sean know.                          Hayaki Saito
-  isn't, let Sean know.                          Johan Duparc
+                                                 Johan Duparc
                                                  Ronny Chevalier
                                                  Michal Cichon
+                                                 Tero Hanninen
+
+License:
+   This software is in the public domain. Where that dedication is not
+   recognized, you are granted a perpetual, irrevocable license to copy
+   and modify this file as you see fit.
+
 */
 
 #ifndef STBI_INCLUDE_STB_IMAGE_H
@@ -640,6 +651,9 @@ static stbi_uc *stbi__pic_load(stbi__context *s, int *x, int *y, int *comp, int
 static int      stbi__gif_test(stbi__context *s);
 static stbi_uc *stbi__gif_load(stbi__context *s, int *x, int *y, int *comp, int req_comp);
 static int      stbi__gif_info(stbi__context *s, int *x, int *y, int *comp);
+static int      stbi__pnm_test(stbi__context *s);
+static stbi_uc *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp);
+static int      stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp);
 
 
 // this is not threadsafe
@@ -694,6 +708,7 @@ static unsigned char *stbi_load_main(stbi__context *s, int *x, int *y, int *comp
    if (stbi__gif_test(s))  return stbi__gif_load(s,x,y,comp,req_comp);
    if (stbi__psd_test(s))  return stbi__psd_load(s,x,y,comp,req_comp);
    if (stbi__pic_test(s))  return stbi__pic_load(s,x,y,comp,req_comp);
+   if (stbi__pnm_test(s))  return stbi__pnm_load(s,x,y,comp,req_comp);
 
    #ifndef STBI_NO_HDR
    if (stbi__hdr_test(s)) {
@@ -5480,6 +5495,112 @@ static int stbi__pic_info(stbi__context *s, int *x, int *y, int *comp)
    return 1;
 }
 
+// *************************************************************************************************
+// Portable Gray Map and Portable Pixel Map loader
+// by Ken Miller
+//
+// PGM: http://netpbm.sourceforge.net/doc/pgm.html
+// PPM: http://netpbm.sourceforge.net/doc/ppm.html
+//
+// Known limitations:
+//    Does not support comments in the header section
+//    Does not support ASCII image data (formats P2 and P3)
+//    Does not support 16-bit-per-channel
+
+static int      stbi__pnm_test(stbi__context *s)
+{
+   char p, t;
+   p = (char) stbi__get8(s);
+   t = (char) stbi__get8(s);
+   if (p != 'P' || (t != '5' && t != '6')) {
+       stbi__rewind( s );
+       return 0;
+   }
+   return 1;
+}
+
+static stbi_uc *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp)
+{
+   stbi_uc *out;
+   if (!stbi__pnm_info(s, (int *)&s->img_x, (int *)&s->img_y, (int *)&s->img_n))
+      return 0;
+   *x = s->img_x;
+   *y = s->img_y;
+   *comp = s->img_n;
+
+   out = (stbi_uc *) stbi__malloc(s->img_n * s->img_x * s->img_y);
+   if (!out) return stbi__errpuc("outofmem", "Out of memory");
+   stbi__getn(s, out, s->img_n * s->img_x * s->img_y);
+
+   if (req_comp && req_comp != s->img_n) {
+      out = stbi__convert_format(out, s->img_n, req_comp, s->img_x, s->img_y);
+      if (out == NULL) return out; // stbi__convert_format frees input on failure
+   }
+   return out;
+}
+
+static int      stbi__pnm_isspace(char c)
+{
+   return c == ' ' || c == '\t' || c == '\n' || c == '\v' || c == '\f' || c == '\r';
+}
+
+static void     stbi__pnm_skip_whitespace(stbi__context *s, char *c)
+{
+   while (!stbi__at_eof(s) && stbi__pnm_isspace(*c))
+      *c = (char) stbi__get8(s);
+}
+
+static int      stbi__pnm_isdigit(char c)
+{
+   return c >= '0' && c <= '9';
+}
+
+static int      stbi__pnm_getinteger(stbi__context *s, char *c)
+{
+   int value = 0;
+
+   while (!stbi__at_eof(s) && stbi__pnm_isdigit(*c)) {
+      value = value*10 + (*c - '0');
+      *c = (char) stbi__get8(s);
+   }
+
+   return value;
+}
+
+static int      stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp)
+{
+   int maxv;
+   char c, p, t;
+
+   stbi__rewind( s );
+
+   // Get identifier
+   p = (char) stbi__get8(s);
+   t = (char) stbi__get8(s);
+   if (p != 'P' || (t != '5' && t != '6')) {
+       stbi__rewind( s );
+       return 0;
+   }
+
+   *comp = (t == '6') ? 3 : 1;  // '5' is 1-component .pgm; '6' is 3-component .ppm
+
+   c = (char) stbi__get8(s);
+   stbi__pnm_skip_whitespace(s, &c);
+
+   *x = stbi__pnm_getinteger(s, &c); // read width
+   stbi__pnm_skip_whitespace(s, &c);
+
+   *y = stbi__pnm_getinteger(s, &c); // read height
+   stbi__pnm_skip_whitespace(s, &c);
+
+   maxv = stbi__pnm_getinteger(s, &c);  // read max value
+
+   if (maxv > 255)
+      return stbi__err("max value > 255", "PPM image not 8-bit");
+   else
+      return 1;
+}
+
 static int stbi__info_main(stbi__context *s, int *x, int *y, int *comp)
 {
    if (stbi__jpeg_info(s, x, y, comp))
@@ -5494,6 +5615,8 @@ static int stbi__info_main(stbi__context *s, int *x, int *y, int *comp)
        return 1;
    if (stbi__pic_info(s, x, y, comp))
        return 1;
+   if (stbi__pnm_info(s, x, y, comp))
+       return 1;
    #ifndef STBI_NO_HDR
    if (stbi__hdr_info(s, x, y, comp))
        return 1;
@@ -5545,6 +5668,10 @@ STBIDEF int stbi_info_from_callbacks(stbi_io_callbacks const *c, void *user, int
 
 /*
    revision history:
+      1.49 (2014-12-25) optimize JPG, incl. x86 SIMD (ryg)
+                        PGM/PPM support (Ken Miller)
+                        STBI_MALLOC,STBI_REALLOC,STBI_FREE
+                        stbi_load_into() -- load into pre-defined memory
       1.48 (2014-12-14) fix incorrectly-named assert()
       1.47 (2014-12-14) 1/2/4-bit PNG support, both direct and paletted (Omar Cornut & stb)
                         optimize PNG (ryg)