the kernel-specific functions can fetch and use additional data it may need

Signed-off-by: Mattias Andrée <maandree@member.fsf.org>

7 files changed, 42 insertions, 18 deletions

diff --git a/src/kern-linux.c b/src/kern-linux.c
index 00930f1..7e31d1b 100644
--- a/src/kern-linux.c
+++ b/src/kern-linux.c
@@ -71,10 +71,13 @@ get_fbpath (int altpath, int fbno)
  * @param   fbpath  The path to the framebuffer device..
  * @param   width   Output parameter for the width of the image.
  * @param   height  Output parameter for the height of the image.
+ * @parma   data    Additional data to pass to `convert_fb_to_pnm`
+ *                  and `convert_fb_to_png`.
  * @return          Zero on success, -1 on error.
  */
 int
-measure (int fbno, char *restrict fbpath, long *restrict width, long *restrict height)
+measure (int fbno, char *restrict fbpath, long *restrict width,
+	 long *restrict height, void **restrict data)
 {
   static char buf[sizeof (SYSDIR "/class/graphics/fb/virtual_size") + 3 * sizeof(int)];
   /* The string "/class/graphics/fb/virtual_size" is large enought for the call (*) "*/
@@ -126,11 +129,12 @@ measure (int fbno, char *restrict fbpath, long *restrict width, long *restrict h
  *                      (a whole number of pixels where available,)
  *                      otherwise, set to the number of bytes a
  *                      pixel is encoded.
+ * @param   data        Data from `measure`.
  * @return              Zero on success, -1 on error.
  */
 int
-convert_fb_to_pnm (FILE *restrict file, const char *restrict buf,
-		   size_t n, size_t *restrict adjustment)
+convert_fb_to_pnm (FILE *restrict file, const char *restrict buf, size_t n,
+		   size_t *restrict adjustment, void *restrict data)
 {
   const uint32_t *restrict pixel;
   int r, g, b;
@@ -169,10 +173,12 @@ convert_fb_to_pnm (FILE *restrict file, const char *restrict buf,
  *                      pixel is encoded.
  * @param   state       Use this to keep track of where in the you
  *                      stopped. It will be 0 on the first call.
+ * @param   data        Data from `measure`.
  * @return              Zero on success, -1 on error.
  */
 int convert_fb_to_png (png_struct *pngbuf, png_byte *restrict pixbuf, const char *restrict buf,
-		       size_t n, long width3, size_t *restrict adjustment, long *restrict state)
+		       size_t n, long width3, size_t *restrict adjustment, long *restrict state,
+		       void *restrict data)
 {
   const uint32_t *restrict pixel;
   int r, g, b;
diff --git a/src/kern.h b/src/kern.h
index 8c2adf0..5975831 100644
--- a/src/kern.h
+++ b/src/kern.h
@@ -58,9 +58,12 @@ char *get_fbpath (int altpath, int fbno);
  * @param   fbpath  The path to the framebuffer device..
  * @param   width   Output parameter for the width of the image.
  * @param   height  Output parameter for the height of the image.
+ * @parma   data    Additional data to pass to `convert_fb_to_pnm`
+ *                  and `convert_fb_to_png`.
  * @return          Zero on success, -1 on error.
  */
-int measure (int fbno, char *restrict fbpath, long *restrict width, long *restrict height);
+int measure (int fbno, char *restrict fbpath, long *restrict width,
+	     long *restrict height, void **restrict data);
 
 /**
  * Convert read data from a framebuffer to PNM pixel data.
@@ -72,10 +75,11 @@ int measure (int fbno, char *restrict fbpath, long *restrict width, long *restri
  *                      (a whole number of pixels where available,)
  *                      otherwise, set to the number of bytes a
  *                      pixel is encoded.
+ * @param   data        Data from `measure`.
  * @return              Zero on success, -1 on error.
  */
-int convert_fb_to_pnm (FILE *restrict file, const char *restrict buf,
-		       size_t n, size_t *restrict adjustment);
+int convert_fb_to_pnm (FILE *restrict file, const char *restrict buf, size_t n,
+		       size_t *restrict adjustment, void *restrict data);
 
 /**
  * Convert read data from a framebuffer to PNG pixel data.
@@ -90,8 +94,10 @@ int convert_fb_to_pnm (FILE *restrict file, const char *restrict buf,
  *                      pixel is encoded.
  * @param   state       Use this to keep track of where in the you
  *                      stopped. It will be 0 on the first call.
+ * @param   data        Data from `measure`.
  * @return              Zero on success, -1 on error.
  */
 int convert_fb_to_png (png_struct *pngbuf, png_byte *restrict pixbuf, const char *restrict buf,
-		       size_t n, long width3, size_t *restrict adjustment, long *restrict state);
+		       size_t n, long width3, size_t *restrict adjustment, long *restrict state,
+		       void *restrict data);
 
diff --git a/src/png.c b/src/png.c
index b0da466..c66df5e 100644
--- a/src/png.c
+++ b/src/png.c
@@ -37,10 +37,12 @@
  * @param   width   The width of the image.
  * @param   height  The height of the image.
  * @param   imgfd   The file descriptor connected to conversion process's stdin.
+ * @param   data    Additional data for `convert_fb_to_pnm`
+ *                  and `convert_fb_to_png`.
  * @return          Zero on success, -1 on error.
  */
 int
-save_png (int fbfd, long width, long height, int imgfd)
+save_png (int fbfd, long width, long height, int imgfd, void *restrict data)
 {
   char buf[8 << 10];
   FILE *file = NULL;
@@ -94,7 +96,7 @@ save_png (int fbfd, long width, long height, int imgfd)
       
       /* Convert read pixels. */
       if (convert_fb_to_png (pngbuf, pixbuf, buf, (size_t)got,
-			     width3, &adjustment, &state) < 0)
+			     width3, &adjustment, &state, data) < 0)
 	goto fail;
       
       /* If we read a whole number of pixels, reset the buffer, otherwise,
diff --git a/src/png.h b/src/png.h
index b621234..0f5d93f 100644
--- a/src/png.h
+++ b/src/png.h
@@ -58,8 +58,10 @@
  * @param   width   The width of the image.
  * @param   height  The height of the image.
  * @param   imgfd   The file descriptor connected to conversion process's stdin.
+ * @param   data    Additional data for `convert_fb_to_pnm`
+ *                  and `convert_fb_to_png`.
  * @return          Zero on success, -1 on error.
  */
 int
-save_png (int fbfd, long width, long height, int imgfd);
+save_png (int fbfd, long width, long height, int imgfd, void *restrict data);
 
diff --git a/src/pnm.c b/src/pnm.c
index da9dd3a..86fa738 100644
--- a/src/pnm.c
+++ b/src/pnm.c
@@ -55,10 +55,12 @@ const char* inttable[] =
  * @param   width   The width of the image.
  * @param   height  The height of the image.
  * @param   imgfd   The file descriptor connected to conversion process's stdin.
+ * @param   data    Additional data for `convert_fb_to_pnm`
+ *                  and `convert_fb_to_png`.
  * @return          Zero on success, -1 on error.
  */
 int
-save_pnm (int fbfd, long width, long height, int imgfd)
+save_pnm (int fbfd, long width, long height, int imgfd, void *restrict data)
 {
   char buf[8 << 10];
   FILE *file = NULL;
@@ -88,7 +90,7 @@ save_pnm (int fbfd, long width, long height, int imgfd)
       got += off;
       
       /* Convert read pixels. */
-      if (convert_fb_to_pnm (file, buf, (size_t)got, &adjustment) < 0)
+      if (convert_fb_to_pnm (file, buf, (size_t)got, &adjustment, data) < 0)
 	goto fail;
       
       /* If we read a whole number of pixels, reset the buffer, otherwise,
diff --git a/src/pnm.h b/src/pnm.h
index 9721d4c..f13972c 100644
--- a/src/pnm.h
+++ b/src/pnm.h
@@ -54,7 +54,9 @@ extern const char* inttable[];
  * @param   width   The width of the image.
  * @param   height  The height of the image.
  * @param   imgfd   The file descriptor connected to conversion process's stdin.
+ * @param   data    Additional data for `convert_fb_to_pnm`
+ *                  and `convert_fb_to_png`.
  * @return          Zero on success, -1 on error.
  */
-int save_pnm (int fbfd, long width, long height, int imgfd);
+int save_pnm (int fbfd, long width, long height, int imgfd, void *restrict data);
 
diff --git a/src/scrotty.c b/src/scrotty.c
index 4bc6982..32b2168 100644
--- a/src/scrotty.c
+++ b/src/scrotty.c
@@ -71,10 +71,13 @@ static int try_alt_fbpath = 0;
  * @param   width     The width of the image.
  * @param   height    The height of the image.
  * @param   raw       Save in PNM?
+ * @param   data      Additional data for `convert_fb_to_pnm`
+ *                    and `convert_fb_to_png`.
  * @return            Zero on success, -1 on error.
  */
 static int
-save (const char *fbpath, const char *imgpath, long width, long height, int raw)
+save (const char *fbpath, const char *imgpath, long width,
+      long height, int raw, void *restrict data)
 {
   int imgfd = -1, fbfd;
   int saved_errno;
@@ -91,7 +94,7 @@ save (const char *fbpath, const char *imgpath, long width, long height, int raw)
     FILE_FAILURE (fbpath);
   
   /* Save image. */
-  if ((raw ? save_pnm : save_png) (fbfd, width, height, imgfd) < 0)
+  if ((raw ? save_pnm : save_png) (fbfd, width, height, imgfd, data) < 0)
     goto fail;
   
   close (fbfd);
@@ -194,6 +197,7 @@ save_fb (int fbno, int raw, const char *filepattern, const char *execpattern)
   char *fbpath; /* Statically allocate string is returned. */
   char *execargs = NULL;
   long width, height;
+  void *data = NULL;
   int i, rc = 0, saved_errno = 0;
   
   /* Get pathname for framebuffer, and stop if we have read all existing ones. */
@@ -202,7 +206,7 @@ save_fb (int fbno, int raw, const char *filepattern, const char *execpattern)
     return 1;
   
   /* Get the size of the framebuffer. */
-  if (measure (fbno, fbpath, &width, &height) < 0)
+  if (measure (fbno, fbpath, &width, &height, &data) < 0)
     goto fail;
   
   /* Get output pathname. */
@@ -220,7 +224,7 @@ save_fb (int fbno, int raw, const char *filepattern, const char *execpattern)
     }
   
   /* Take a screenshot of the current framebuffer. */
-  if (save (fbpath, imgpath, width, height, raw) < 0)
+  if (save (fbpath, imgpath, width, height, raw, data) < 0)
     goto fail;
   fprintf (stderr, _("Saved framebuffer %i to %s.\n"), fbno, imgpath);