osmq

commit 1198f783db53c8561ca78bb9240b749eb0a00e64
parent 0e5e6cec1ace21d11e4b3fd2568b3a7aa0a7cd54
Author: Tomas Hlavaty <tom@logand.com>
Date:   Thu, 12 Sep 2019 15:44:23 +0200

readability

Diffstat:
M
osmq
 | 
3
+--
M
osmtile.c
 | 
184
++++++++++++++++++++++++++++++++++---------------------------------------------

2 files changed, 79 insertions(+), 108 deletions(-)
diff --git a/osmq b/osmq
@@ -1,6 +1,5 @@
 #!/usr/bin/env bash
-set -e
-set -o pipefail
+set -euo pipefail
 read \
     LAT \
     LON \
diff --git a/osmtile.c b/osmtile.c
@@ -5,6 +5,8 @@
 #include <sys/wait.h>
 #include <unistd.h>
 
+#define fail(z, ...) ({fprintf(stderr, __VA_ARGS__); exit(z);})
+
 /* https://wiki.openstreetmap.org/wiki/Slippy_map_tilenames */
 static int long2tilex(double lon, int z) {
   return (int)(floor((lon + 180.0) / 360.0 * pow(2.0, z)));
@@ -24,53 +26,54 @@ static double tiley2lat(int y, int z) {
 }
 
 static int zoom_from_string(char *string) {
-  int z;
-  if(!string) goto fail;
-  if(1 != sscanf(string, "%d", &z)) goto fail;
-  if(z < 0 || 18 < z) goto fail;
-  return z;
- fail:
-  fprintf(stderr, "expected zoom 0 <= %s <= 18\n", string);
-  exit(1);
+  if(string) {
+    int z;
+    if(1 == sscanf(string, "%d", &z)) {
+      if(0 <= z && z <= 18) {
+        return z;
+      }
+    }
+  }
+  fail(1, "expected zoom 0 <= %s <= 18\n", string);
 }
 
-static int lat(int argc, char *argv[]) {
+static int main_lat(int argc, char *argv[]) {
   int z = zoom_from_string(argv[0]);
   char *value = argv[1];
-  if(!value) goto fail;
-  int y;
-  if(1 != sscanf(value, "%d", &y)) goto fail;
-  printf("%lf\n", tiley2lat(y, z));
-  return 0;
- fail:
-  fprintf(stderr, "unexpected y %s\n", value);
-  return 1;
+  if(value) {
+    int y;
+    if(1 == sscanf(value, "%d", &y)) {
+      printf("%lf\n", tiley2lat(y, z));
+      return 0;
+    }
+  }
+  fail(1, "unexpected y %s\n", value);
 }
 
-static int lon(int argc, char *argv[]) {
+static int main_lon(int argc, char *argv[]) {
   int z = zoom_from_string(argv[0]);
   char *value = argv[1];
-  if(!value) goto fail;
-  int x;
-  if(1 != sscanf(value, "%d", &x)) goto fail;
-  printf("%lf\n", tilex2long(x, z));
-  return 0;
- fail:
-  fprintf(stderr, "unexpected x %s\n", value);
-  return 1;
+  if(value) {
+    int x;
+    if(1 == sscanf(value, "%d", &x)) {
+      printf("%lf\n", tilex2long(x, z));
+      return 0;
+    }
+  }
+  fail(1, "unexpected x %s\n", value);
 }
 
 static double lon_from_string(char *string) {
-  if(!string) goto fail;
-  double z;
-  if(1 != sscanf(string, "%lf", &z)) goto fail;
-  return z;
- fail:
-  fprintf(stderr, "unexpected longitude %s\n", string);
-  exit(1);
+  if(string) {
+    double z;
+    if(1 == sscanf(string, "%lf", &z)) {
+      return z;
+    }
+  }
+  fail(1, "unexpected longitude %s\n", string);
 }
 
-static int x(int argc, char *argv[]) {
+static int main_x(int argc, char *argv[]) {
   int z = zoom_from_string(argv[0]);
   double lon = lon_from_string(argv[1]);
   printf("%d\n", long2tilex(lon, z));
@@ -78,16 +81,16 @@ static int x(int argc, char *argv[]) {
 }
 
 static double lat_from_string(char *string) {
-  if(!string) goto fail;
-  double z;
-  if(1 != sscanf(string, "%lf", &z)) goto fail;
-  return z;
- fail:
-  fprintf(stderr, "unexpected latitude %s\n", string);
-  exit(1);
+  if(string) {
+    double z;
+    if(1 == sscanf(string, "%lf", &z)) {
+      return z;
+    }
+  }
+  fail(1, "unexpected latitude %s\n", string);
 }
 
-static int y(int argc, char *argv[]) {
+static int main_y(int argc, char *argv[]) {
   int z = zoom_from_string(argv[0]);
   double lat = lat_from_string(argv[1]);
   printf("%d\n", lat2tiley(lat, z));
@@ -106,19 +109,13 @@ static int probe(char *path) {
 static void run(char *args[]) {
   int stat;
   switch(fork()) {
-  case -1:
-    fprintf(stderr, "fork failed\n");
-    exit(1);
+  case -1: fail(1, "fork failed\n");
   case 0:
     execvp(*args, args);
-    fprintf(stderr, "exec %s failed\n", *args);
-    exit(1);
+    fail(1, "exec %s failed\n", *args);
   default:
     wait(&stat);
-    if(stat) {
-      fprintf(stderr, "%s failed %d\n", *args, stat);
-      exit(1);
-    }
+    if(stat) fail(1, "%s failed %d\n", *args, stat);
   }
 }
 
@@ -137,45 +134,27 @@ static int cached_file(int z, int x, int y, char *dir, char file[4096]) {
   if(max < y) y = 0;
   char d[4096];
   int n = snprintf(d, sizeof(d), "%s/%d/%d", dir, z, x);
-  if(n < 0 || sizeof(d) < n) {
-    fprintf(stderr, "directory path error\n");
-    exit(1);
-  }
+  if(n < 0 || sizeof(d) < n) fail(1, "directory path error\n");
   n = snprintf(file, 4096, "%s/%d.png", d, y);
-  if(n < 0 || 4096 < n) {
-    fprintf(stderr, "file path error\n");
-    exit(1);
-  }
+  if(n < 0 || 4096 < n) fail(1, "file path error\n");
   if(probe(file)) return 1;
   {
     char url[4096];
     int n = snprintf(url, sizeof(url), "https://tile.openstreetmap.org/%d/%d/%d.png", z, x, y);
-    if(n < 0 || sizeof(url) < n) {
-      fprintf(stderr, "url error\n");
-      exit(1);
-    }
+    if(n < 0 || sizeof(url) < n) fail(1, "url error\n");
     char *args1[] = {"mkdir", "-p", d, NULL};
     run(args1);
     char *args2[] = {"curl", "-s", "-o", file, url, NULL};
     run(args2);
-    if(!probe(file)) {
-      fprintf(stderr, "cached file '%s' not found\n", file);
-      exit(1);
-    }
+    if(!probe(file)) fail(1, "cached file '%s' not found\n", file);
   }
   return 1;
 }
 
 static void screen_size(int *w, int *h) {
   FILE *f = fopen("/sys/class/graphics/fb0/virtual_size", "r");
-  if(!f) {
-    fprintf(stderr, "unknown screen\n");
-    exit(1);
-  }
-  if(2 != fscanf(f, "%d,%d", w, h)) {
-    fprintf(stderr, "unknown screen size\n");
-    exit(1);
-  }
+  if(!f) fail(1, "unknown screen\n");
+  if(2 != fscanf(f, "%d,%d", w, h)) fail(1, "unknown screen size\n");
   fclose(f);
 }
 
@@ -204,7 +183,7 @@ static unsigned char key(int timeout) {
   return c;
 }
 
-static int tty(int argc, char *argv[]) {
+static int main_tty(int argc, char *argv[]) {
   int width, height;
   screen_size(&width, &height);
   // popen r stty size -> w h
@@ -214,10 +193,7 @@ static int tty(int argc, char *argv[]) {
   run(args0b);
   atexit(cleanup);
   char *dir = argv[0];
-  if(!dir) {
-    fprintf(stderr, "unexpected dir %s\n", dir);
-    return 1;
-  }
+  if(!dir) fail(1, "unexpected dir %s\n", dir);
   int z0 = zoom_from_string(argv[1]);
   double a0 = lat_from_string(argv[2]);
   double o0 = lon_from_string(argv[3]);
@@ -227,10 +203,7 @@ static int tty(int argc, char *argv[]) {
   int y = lat2tiley(a, z);
   for(;;) {
     FILE *p = popen("w3mimgdisplay", "w");
-    if(!p) {
-      fprintf(stderr, "popen w3mimgdisplay failed\n");
-      exit(1);
-    }
+    if(!p) fail(1, "popen w3mimgdisplay failed\n");
     int full = 1;
     for(int i = 0; i < 3; i++) {
       for(int j = 0; j < 3; j++) {
@@ -362,14 +335,14 @@ static int tty(int argc, char *argv[]) {
   }
 }
 
-static int version(int argc, char *argv[]) {
+static int main_version(int argc, char *argv[]) {
   printf("%s\n",
 #include "VERSION"
          );
   return 0;
 }
 
-static int help(int argc, char *argv[]) {
+static int main_help(int argc, char *argv[]) {
   printf("usage: osmtile cmd args\n");
   printf("  lat zoom y\n");
   printf("  lon zoom x\n");
@@ -383,26 +356,25 @@ static int help(int argc, char *argv[]) {
 
 int main(int argc, char *argv[]) {
   char *cmd = argv[1];
-  if(!cmd) goto fail;
-  static const struct {
-    char *cmd;
-    int (*fn)(int argc, char *argv[]);
-  } dispatch[] = {
-                  {"lat", lat},
-                  {"lon", lon},
-                  {"x", x},
-                  {"y", y},
-                  {"tty", tty},
-                  {"--version", version},
-                  {"--help", help},
-                  {NULL}
-  };
-  for(int i = 0; dispatch[i].cmd; i++) {
-    if(!strcmp(dispatch[i].cmd, cmd)) {
-      return dispatch[i].fn(argc - 2, &argv[2]);
+  if(cmd) {
+    static const struct {
+      char *cmd;
+      int (*fn)(int argc, char *argv[]);
+    } dispatch[] = {
+                    {"lat", main_lat},
+                    {"lon", main_lon},
+                    {"x", main_x},
+                    {"y", main_y},
+                    {"tty", main_tty},
+                    {"--version", main_version},
+                    {"--help", main_help},
+                    {NULL}
+    };
+    for(int i = 0; dispatch[i].cmd; i++) {
+      if(!strcmp(dispatch[i].cmd, cmd)) {
+        return dispatch[i].fn(argc - 2, &argv[2]);
+      }
     }
   }
- fail:
-  fprintf(stderr, "unexpected command %s\n", cmd);
-  return 1;
+  fail(1, "unexpected command %s\n", cmd);
 }