From 8df0f582a3a589afd155137685b410a69267ff9c Mon Sep 17 00:00:00 2001
From: Yi Hong <zouzou0208@gmail.com>
Date: Wed, 10 May 2023 22:08:21 +0800
Subject: [PATCH] record: skip whitespaces after shebang for scripts

Python tracing won't work when the shebang line has a space like below:

  #! /usr/bin/env python3

This patch makes uftrace to understand the above shebang as well.

Fixed: #1690
Signed-off-by: Yi Hong <zouzou0208@gmail.com>
---
 cmds/record.c |  2 +-
 utils/utils.c | 31 +++++++++++++++++++++++++++++++
 utils/utils.h |  2 ++
 3 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/cmds/record.c b/cmds/record.c
index 453a6c584..c80013994 100644
--- a/cmds/record.c
+++ b/cmds/record.c
@@ -1608,7 +1608,7 @@ static void check_binary(struct uftrace_opts *opts)
 		pr_err("Cannot read '%s'", opts->exename);
 
 	if (memcmp(elf_ident, ELFMAG, SELFMAG)) {
-		char *script = check_script_file(opts->exename);
+		char *script = str_ltrim(check_script_file(opts->exename));
 		char *p;
 
 		if (script == NULL)
diff --git a/utils/utils.c b/utils/utils.c
index 592b3df40..cd49bb8da 100644
--- a/utils/utils.c
+++ b/utils/utils.c
@@ -594,6 +594,37 @@ char *strjoin(char *left, char *right, const char *delim)
 	return new;
 }
 
+/**
+ * str_ltrim - to trim left spaces
+ * @str: input string
+ *
+ * This function make @str to left trimmed @str
+ */
+char *str_ltrim(char *str)
+{
+	if (!str)
+		return NULL;
+	while (isspace((unsigned char)*str)) {
+		str++;
+	}
+	return str;
+}
+
+/**
+ * str_rtrim - to trim right spaces
+ * @str: input string
+ *
+ * This function make @str to right trimmed @str
+ */
+char *str_rtrim(char *str)
+{
+	char *p = strchr(str, '\0');
+	while (--p >= str && isspace(*p))
+		;
+	*(p + 1) = '\0';
+	return str;
+}
+
 /**
  * strv_split - split given string and construct a string vector
  * @strv:  string vector
diff --git a/utils/utils.h b/utils/utils.h
index fb0d8c4ed..393def811 100644
--- a/utils/utils.h
+++ b/utils/utils.h
@@ -389,6 +389,8 @@ void strv_append(struct strv *strv, const char *str);
 void strv_replace(struct strv *strv, int idx, const char *str);
 char *strv_join(struct strv *strv, const char *delim);
 void strv_free(struct strv *strv);
+char *str_ltrim(char *str);
+char *str_rtrim(char *str);
 
 char **parse_cmdline(char *cmd, int *argc);
 void free_parsed_cmdline(char **argv);