Replace support for step/rate with durationsupport_duration

This replaces the rate and step configuration swith the single duration
configuration. This automatically calculates step size by dividing max
brightness into intervals of 1/300th. On systems where this operation
yields a less than 1 number, 1 is assumed.

This also removes the rate configuration by automatically setting it to
the duration divided by the step count (step count being step size
divided into distance).

2 files changed, 53 insertions, 92 deletions

diff --git a/sample.conf b/sample.conf
index da257f9..08d2604 100644
--- a/sample.conf
+++ b/sample.conf
@@ -1,3 +1,2 @@
 level = 150
-rate  = 20
-step  = 12
+duration = 500
diff --git a/src/main.c b/src/main.c
index bcd76db..9ee733f 100644
--- a/src/main.c
+++ b/src/main.c
@@ -15,9 +15,7 @@
  * along with noteless.  If not, see <http://www.gnu.org/licenses/>.
  */
 #include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <time.h>
+#include <unistd.h>
 #include <errno.h>
 #include <sys/file.h>
 
@@ -31,22 +29,20 @@
 
 
 struct props {
-  int lvl;  // Destination brightness
-  int step; // Step size
-  int rate; // Time in milliseconds between steps
-  int max;  // Maximum brightness of screen device
-  int cur;  // Current brightness prior to fade operation
+  int lvl;      // Destination brightness
+  int max;      // Maximum brightness of screen device
+  int cur;      // Current brightness prior to fade operation
+  int duration; // Duration to fade through
   char filebrightness[512]; // Path to the sysfs ent for brightness
   char filemax_bright[512]; // Path to the sysfs ent for max brightness
 };
 
 
 void props_new(struct props* p) {
-  p->lvl  = -1;
-  p->step = -1;
-  p->rate = -1;
-  p->max  = -1;
-  p->cur  = -1;
+  p->lvl      = 200;
+  p->max      = -1;
+  p->cur      = -1;
+  p->duration = 500;
   p->filebrightness[0] = '\0';
   p->filemax_bright[0] = '\0';
 }
@@ -99,29 +95,15 @@ int fgeti(char* path) {
  * returns: Success (0) or failure (-1)
  */
 int fade(struct props* props) {
-  struct timespec tim, tim2;
-  int sec;  // Number of seconds to sleep
-  int msec; // Number of milliseconds to sleep (less than 1 second)
-  int direction = 0; // Direction of fade. Positive for up, negative for down
-  int opcount   = 0;
+  int direction = 0;             // Direction of fade. 1 for up, -1 for down
+  int step = props->max / 300;   // Calculate what 1/300 of max is for step
+  int rate = 0;                  // Duration / step count
+  int steps = 0;                 // How many steps to cover the distance
 
-  sec = props->rate / 1000;
-  msec = props->rate - (sec * 1000);
-
-  tim.tv_sec = sec;
-  tim.tv_nsec = 1000000 * msec;
-
-  // Determine direction
-  if(props->lvl > props->cur) {
-    // Dest brightness is higher than current
-    direction = 1;
-    opcount = (props->lvl - props->cur) / props->step;
-  } else if(props->lvl < props->cur) {
-    // Dest brightness is lower than current
-    direction = -1;
-    opcount = (props->cur - props->lvl) / props->step;
-  }
+  if(step < 1)
+    step = 1;
 
+  // Make sure we can open the file
   FILE* fd = fopen(props->filebrightness, "w");
   if(! fd) {
     if(errno == EACCES) {
@@ -132,28 +114,33 @@ int fade(struct props* props) {
     return -1;
   }
 
-  // Lock the file descriptor so we can't have conflicting brightness change
-  // operations
+  // Determine direction
+  if(props->lvl > props->cur) {
+    direction = 1;
+    steps = (props->lvl - props->cur) / step;
+  } else if(props->lvl < props->cur) {
+    direction = -1;
+    steps = (props->cur - props->lvl) / step;
+  }
+  if(steps == 0)
+    steps = 1;   // Ensure no divide by zero operations happen
+  rate = (props->duration / steps) * 1000;
+
+  // Lock the file descriptor so we can't have conflicting write operations
   if(flock(fileno(fd), LOCK_EX | LOCK_NB) != 0) {
     fprintf(stderr, "Could not obtain brightness file lock\n");
     fclose(fd);
     return -1;
   }
 
-  while(opcount > 0) {
-    nanosleep(&tim, &tim2);
-
+  while(steps > 0) {
+    usleep(rate);
     // Write the new brightness to the brightness file
     fprintf(fd, "%d\n", props->cur);
-
-    // Flush the toil...er...buffer!
     fflush(fd);
-
-    props->cur += props->step * direction;
-    opcount--;
+    props->cur += step * direction;
+    steps--;
   }
-
-  // Do not need to explicitly release the file lock
   fclose(fd);
   return 0;
 }
@@ -176,11 +163,10 @@ void usage() {
 "  luminous --rate 10 --step 8 --level [+-]400\n"
 "\n"
 "Arguments:\n"
-"  -h,--help    Print this helptext\n"
-"  -s,--step    Fade step (default: 6)\n"
-"  -r,--rate    Time in milliseconds between fade steps (default: 10)\n"
-"  -l,--level   Brightness level to change to. Supports absolute values and\n"
-"               relative values prefixed with + and -.\n"
+"  -h,--help     Print this helptext\n"
+"  -d,--duration Duration of the fade (default: 500 ms)\n"
+"  -l,--level    Brightness level to change to. Supports absolute values and\n"
+"                relative values prefixed with + and -.\n"
 "  -V,--version Print program version"
 "\n\n"
 );
@@ -210,12 +196,10 @@ int parseargs(struct props* out, int argc, char* argv[]) {
   out->max = fgeti(out->filemax_bright);
 
   for(i = 0; i < argc; i++) {
-    if(strcmp(argv[i], "-r") == 0 || strcmp(argv[i], "--rate") == 0) {
+    if(strcmp(argv[i], "-d") == 0 || strcmp(argv[i], "--duration") == 0) {
       i++;
-      out->rate = atoi(argv[i]);
-    } else if(strcmp(argv[i], "-s") == 0 || strcmp(argv[i], "--step") == 0) {
-      i++;
-      out->step = atoi(argv[i]);
+      out->duration = atoi(argv[i]);
+
     } else if(strcmp(argv[i], "-l") == 0 || strcmp(argv[i], "--level") == 0) {
       i++;
       // Account for relative and absolute increments and decrements
@@ -226,61 +210,44 @@ int parseargs(struct props* out, int argc, char* argv[]) {
       } else {
         out->lvl = atoi(argv[i]);
       }
+
     } else if(strcmp(argv[i], "-V") == 0 || strcmp(argv[i], "--version") == 0) {
       version_print(stdout);
       return -2;
+
     } else if(strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--help") == 0) {
       usage();
       return -2;
     }
   }
 
-  // Some defaults, if no values are set yet
-  if(out->rate < 0)
-   out->rate = 20;
-  if(out->step < 0)
-   out->step = 12;
-  if(out->lvl == -1)
-    out->lvl = 200;
-
   // Ensure min and max thresholds are respected
-  if(out->lvl > out->max) {
+  if(out->lvl > out->max)
     out->lvl = out->max;
-  } else if(out->lvl < 0) {
+  else if(out->lvl < 0)
     out->lvl = 0;
-  }
   return 0;
 }
 
 
 int config_to_props(char* confpath, struct props* p) {
   struct config c;
-  char lvlbuf[32];  // Buffer to store config value for "level" if found
-  char ratebuf[32]; // Buffer to store config value for "rate" if found
-  char stepbuf[32]; // Buffer to store config value for "step" if found
+  char lvlbuf[32];       // Buffer to store config value for "level" if found
+  char durationbuf[32];  // Buffer to store config value for "duration" if found
 
-  if(config_new(&c, confpath) == 0) {
+  if(config_new(&c, confpath) == 0)
     config_load(&c);
-  } else {
-    // Config file not found, return -2 code
+  else
     return -2;
-  }
 
-  // If the config specifies a "level" key, set it to the props object
+  // Check for and load specific configs
   if(config_get(&c, "level", lvlbuf) == 0)
     p->lvl = atoi(lvlbuf);
-
-  // If the config specifies a "step" key, set it to the props object
-  if(config_get(&c, "step", stepbuf) == 0)
-    p->step = atoi(stepbuf);
-
-  // If the config specifies a "rate" key, set it to the props object
-  if(config_get(&c, "rate", ratebuf) == 0)
-    p->rate = atoi(ratebuf);
+  if(config_get(&c, "duration", lvlbuf) == 0)
+    p->duration = atoi(durationbuf);
 
   // Don't forget to clean up!
   config_free(&c);
-
   return 0;
 }
 
@@ -301,12 +268,7 @@ int main(int argc, char* argv[]) {
   if(parseargs(&p, argc, argv) != 0)
     return 1;
 
-  // Determine if we should fade up or fade down
-  if(p.lvl < 0) {
-    printf("%d\n", p.cur);
-  } else {
-    r = fade(&p);
-  }
+  r = fade(&p);
 
   if(r < 0) {
     fprintf(stderr, "ERROR: Could not open brightness file\n");