GUAC-236: Parse command-line arguments.

src/guacenc/Makefile.am

@@ -34,6 +34,7 @@ noinst_HEADERS =   \
     jpeg.h         \
     layer.h        \
     log.h          \
+    parse.h        \
     png.h          \
     video.h
 
@@ -65,6 +66,7 @@ guacenc_SOURCES =           \
     jpeg.c                  \
     layer.c                 \
     log.c                   \
+    parse.c                 \
     png.c                   \
     video.c
 

src/guacenc/guacenc.c

@@ -25,23 +25,17 @@
 #include "encode.h"
 #include "guacenc.h"
 #include "log.h"
+#include "parse.h"
 
 #include <libavcodec/avcodec.h>
 
+#include <getopt.h>
+#include <stdio.h>
+
 int main(int argc, char* argv[]) {
 
     int i;
 
-    /* Log start */
-    guacenc_log(GUAC_LOG_INFO, "Guacamole video encoder (guacenc) "
-            "version " VERSION);
-
-    /* Abort if no files given */
-    if (argc <= 1) {
-        guacenc_log(GUAC_LOG_INFO, "No input files specified. Nothing to do.");
-        return 0;
-    }
-
     /* Load defaults */
     const char* codec = GUACENC_DEFAULT_CODEC;
     const char* suffix = GUACENC_DEFAULT_SUFFIX;
@@ -49,17 +43,65 @@ int main(int argc, char* argv[]) {
     int height = GUACENC_DEFAULT_HEIGHT;
     int bitrate = GUACENC_DEFAULT_BITRATE;
 
-    /* TODO: Override defaults via command-line arguments */
+    /* Parse arguments */
+    int opt;
+    while ((opt = getopt(argc, argv, "V:s:d:r:")) != -1) {
+
+        /* -V: Video codec */
+        if (opt == 'V')
+            codec = optarg;
+
+        /* -s: Output file suffix */
+        else if (opt == 's')
+            suffix = optarg;
+
+        /* -d: Dimensions */
+        else if (opt == 'd') {
+            if (guacenc_parse_dimensions(optarg, &width, &height)) {
+                guacenc_log(GUAC_LOG_ERROR, "Invalid dimensions.");
+                goto invalid_options;
+            }
+        }
+
+        /* -r: Bitrate (bits per second) */
+        else if (opt == 'r') {
+            if (guacenc_parse_int(optarg, &bitrate)) {
+                guacenc_log(GUAC_LOG_ERROR, "Invalid bitrate.");
+                goto invalid_options;
+            }
+        }
+
+        /* Invalid option */
+        else {
+            goto invalid_options;
+        }
+
+    }
+
+    /* Log start */
+    guacenc_log(GUAC_LOG_INFO, "Guacamole video encoder (guacenc) "
+            "version " VERSION);
+
+    guacenc_log(GUAC_LOG_INFO, "Video will be encoded as \"%s\" at %ix%i "
+            "and %i bps.", codec, width, height, bitrate);
+
+    guacenc_log(GUAC_LOG_INFO, "Output files will end with \".%s\".", suffix);
 
     /* Prepare libavcodec */
     avcodec_register_all();
 
     /* Track number of overall failures */
-    int total_files = argc - 1;
+    int total_files = argc - optind;
     int failures = 0;
 
+    /* Abort if no files given */
+    if (total_files <= 0) {
+        guacenc_log(GUAC_LOG_INFO, "No input files specified. Nothing to do.");
+        return 0;
+    }
+
     /* Encode all input files */
-    for (i = 1; i < argc; i++) {
+    for (i = optind; i < argc; i++) {
 
         /* Get current filename */
         const char* path = argv[i];
@@ -98,5 +140,17 @@ int main(int argc, char* argv[]) {
     /* Encoding complete */
     return 0;
 
+    /* Display usage and exit with error if options are invalid */
+invalid_options:
+
+    fprintf(stderr, "USAGE: %s"
+            " [-d WIDTHxHEIGHT]"
+            " [-s SUFFIX]"
+            " [-V CODEC]"
+            " [-b BITRATE]"
+            " [-f]\n", argv[0]);
+
+    return 1;
+
 }
 

src/guacenc/parse.c

@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2016 Glyptodon, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "config.h"
+
+#include <errno.h>
+#include <limits.h>
+#include <string.h>
+#include <stdlib.h>
+
+int guacenc_parse_int(char* arg, int* i) {
+
+    char* end;
+
+    /* Parse string as an integer */
+    errno = 0;
+    long int value = strtol(arg, &end, 10);
+
+    /* Ignore number if invalid / non-positive */
+    if (errno != 0 || value <= 0 || value > INT_MAX || *end != '\0')
+        return 1;
+
+    /* Store value */
+    *i = value;
+
+    /* Parsing successful */
+    return 0;
+
+}
+
+int guacenc_parse_dimensions(char* arg, int* width, int* height) {
+
+    /* Locate the 'x' within the dimensions string */
+    char* x = strchr(arg, 'x');
+    if (x == NULL)
+        return 1;
+
+    /* Replace 'x' with a null terminator */
+    *x = '\0';
+
+    /* Parse width and height */
+    int w, h;
+    if (guacenc_parse_int(arg, &w) || guacenc_parse_int(x+1, &h))
+        return 1;
+
+    /* Width and height are both valid */
+    *width = w;
+    *height = h;
+
+    return 0;
+
+}
+

src/guacenc/parse.h

@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2016 Glyptodon, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef GUACENC_PARSE_H
+#define GUACENC_PARSE_H
+
+#include "config.h"
+
+/**
+ * Parses a string into a single integer. Only positive integers are accepted.
+ * The input string may be modified during parsing. A value will be stored in
+ * the provided int pointer only if valid.
+ *
+ * @param arg
+ *     The string to parse.
+ *
+ * @param i
+ *     A pointer to the integer in which the parsed value of the given string
+ *     should be stored.
+ *
+ * @return
+ *     Zero if parsing was successful, non-zero if the provided string was
+ *     invalid.
+ */
+int guacenc_parse_int(char* arg, int* i);
+
+/**
+ * Parses a string of the form WIDTHxHEIGHT into individual width and height
+ * integers. The input string may be modified during parsing. Values will be
+ * stored in the provided width and height pointers only if the given
+ * dimensions are valid.
+ *
+ * @param arg
+ *     The string to parse.
+ *
+ * @param width
+ *     A pointer to the integer in which the parsed width component of the
+ *     given string should be stored.
+ *
+ * @param height
+ *     A pointer to the integer in which the parsed height component of the
+ *     given string should be stored.
+ *
+ * @return
+ *     Zero if parsing was successful, non-zero if the provided string was
+ *     invalid.
+ */
+int guacenc_parse_dimensions(char* arg, int* width, int* height);
+
+#endif
+
+