* context.c: add the "swap" command to swap two images in the stack.

git-svn-id: file:///srv/caca.zoy.org/var/lib/svn/libpipi/trunk@2709 92316355-f0b4-4df1-b90c-862c8a59935f

pipi/context.c

@@ -62,7 +62,7 @@ int pipi_command(pipi_context_t *ctx, char const *cmd, ...)
         char const *file;
         va_list ap;
 
-        if(ctx->nimages <= 0)
+        if(ctx->nimages < 1)
             return -1;
         ctx->nimages--;
         va_start(ap, cmd);
@@ -77,7 +77,7 @@ int pipi_command(pipi_context_t *ctx, char const *cmd, ...)
         char const *method;
         va_list ap;
 
-        if(ctx->nimages <= 0)
+        if(ctx->nimages < 1)
             return -1;
         va_start(ap, cmd);
         method = va_arg(ap, char const *);
@@ -119,7 +119,7 @@ int pipi_command(pipi_context_t *ctx, char const *cmd, ...)
         char const *arg;
         va_list ap;
 
-        if(ctx->nimages <= 0)
+        if(ctx->nimages < 1)
             return -1;
         va_start(ap, cmd);
         arg = va_arg(ap, char const *);
@@ -208,14 +208,14 @@ int pipi_command(pipi_context_t *ctx, char const *cmd, ...)
     }
     else if(!strcmp(cmd, "wrap"))
     {
-        if(ctx->nimages <= 0)
+        if(ctx->nimages < 1)
             return -1;
         ctx->images[ctx->nimages - 1]->wrap = 1;
     }
     else if(!strcmp(cmd, "autocontrast"))
     {
         pipi_image_t *tmp;
-        if(ctx->nimages <= 0)
+        if(ctx->nimages < 1)
             return -1;
         tmp = ctx->images[ctx->nimages - 1];
         ctx->images[ctx->nimages - 1] = pipi_autocontrast(tmp);
@@ -223,24 +223,33 @@ int pipi_command(pipi_context_t *ctx, char const *cmd, ...)
     }
     else if(!strcmp(cmd, "gray"))
     {
-        if(ctx->nimages <= 0)
+        if(ctx->nimages < 1)
             return -1;
         pipi_getpixels(ctx->images[ctx->nimages - 1], PIPI_PIXELS_Y_F);
     }
     else if(!strcmp(cmd, "free"))
     {
-        if(ctx->nimages <= 0)
+        if(ctx->nimages < 1)
             return -1;
         ctx->nimages--;
         pipi_free(ctx->images[ctx->nimages]);
     }
     else if(!strcmp(cmd, "dup"))
     {
-        if(ctx->nimages <= 0)
+        if(ctx->nimages < 1)
             return -1;
         ctx->images[ctx->nimages] = pipi_copy(ctx->images[ctx->nimages - 1]);
         ctx->nimages++;
     }
+    else if(!strcmp(cmd, "swap"))
+    {
+        pipi_image_t *tmp;
+        if(ctx->nimages < 2)
+            return -1;
+        tmp = ctx->images[ctx->nimages - 1];
+        ctx->images[ctx->nimages - 1] = ctx->images[ctx->nimages - 2];
+        ctx->images[ctx->nimages - 2] = tmp;
+    }
     else
     {
         return -1;

src/pipi.c

@@ -20,6 +20,11 @@ int main(int argc, char *argv[])
             if(pipi_command(ctx, "dup") != 0)
                 return EXIT_FAILURE;
         }
+        else if(!strcmp(argv[0], "--swap"))
+        {
+            if(pipi_command(ctx, "swap") != 0)
+                return EXIT_FAILURE;
+        }
         else if(!strcmp(argv[0], "--dither"))
         {
             if(argv[1] == NULL)